F-35 Lightning

YouTube - F-35 Lightning

General Specifications
Costs (not including fixing of manufacturing flaws) -
F-35 model A:
F-35 model B:
F-35 model C:
Flight Cost Model A FY 2018:
Primary Function:
F-35B Vertical Thrust:
Weight Empty - F-35A:
Max. Weight- F-35A:
Internal Cannon (model A):
Ordnance non-stealth:
Ordnance A & C stealth:
Ordnance B stealth:
Max G-Ratings:
Wingspan - A & B:
Max. Speed:
Initial Climb:
Combat Radius Internal Fuel- A & C:
First Flight
US$89.2 million ea.
US$115.5 million ea.
US$107.7 million ea.
about US$44,000/hr.
multi role attack
P&W F135
40,000 lbs.
40,500 lbs.
29,300 lbs.
32,300 lbs.
34,800 lbs.
70,000 lbs.
60,000 lbs.
70,000 lbs.
1- 25 mm
18,000 lbs.
5,700 lbs.
3,700 lbs.
51 ft. 5 in.
35 ft. 0 in.
43 ft. 0 in.
1,200 mph
40,000 fpm (est.)
50,000 feet

690 miles
520 miles

The F-35 Lightning, officially Lockheed Martin F-35 Lightning II, is also known as the Joint Strike Fighter or JSF. It is the most expensive airplane project in the history of the world estimated at US$1.196 trillion.  That estimate is the projected cost should the aircraft be used through their 2070 expected life.  The aircraft is primarily produced by Lockheed-Martin along with Northrop Grumman and BAE Systems.  The  mission of the F-35 Lightning is as a multi-role intelligence gathering weapons platform.The aircraft is intended to be a replacement for numerous aging aircraft designs. The United States plans to purchase a combined total of 2,663 aircraft. They are for use by the U.S. Air Force, U.S. Navy, and U.S. Marines in three variants.

F-35 Lightning helmet

F-35 Lightning - Pilot's Helmet

All three F-35 Lightning aircraft use a special pilot's helmet that is custom made and fitted to its individual pilot. This is accomplished by making a three dimension scan of the pilot's head from which milling machines can precisely cut the helmet. Then technicians do a final hand fit on each pilot's head. This is in order to ensure a perfect fit, necessary in preventing neck injuries during extreme maneuvers or an aircraft ejection.

The helmet is made from Kevlar and carbon fiber. It has a polycarbonate visor and has an estimate cost of at least US$400,000 each.

The helmet is designed to give the pilot an all around the aircraft view, and the ability to select the view presented. Information presented on the head up display windscreen of other fighter aircraft is shown on the visor of the helmet. Three options are available to F-35 Lightning pilots for their helmet displays. They are night vision, thermal imagery, and real time video. All are accessible by pressing a button of the aircraft's control stick.

The helmet follows where the pilots eyes are looking so the real time data feed collected by six cameras placed around the aircraft are positioned in exactly the same place on the visor, no matter the head position. The helmet must be custom fitted to the pilot in order to accomplish this.

The camera system enables the pilot to look down and see what is happening directly below the aircraft. It also has the ability to overlay the outside display with targeting or navigation information. The helmet does this by sensing its position relative to the aircraft.

Position sensing is accomplished with the generation of a magnetic field from inside the pilot's seat. When the pilot's head moves, a change in the field is detected by sensors in the helmet.

For targeting, sensors detect the position of the pilot's eyes to determine where he is looking. By using the EOTS (Electro Optical Targeting System) what is presented on the helmet's visor will be collected from sensors around the aircraft. Supplied are suggested ordnance to use, target distance and identity. In addition to sensors, additional gathering of information is done by FLIR (Forward Looking Infrared) and ISTR (Infrared Search and Track Radar. A missile fired from the aircraft will follow the pilot's line of vision, not the path of the aircraft.

It is anticipated that by early 2019 the first production version of a new pilot helmet will be available that is expected to do away with a “green glow” from helmet back lighting that obscures pilots’ vision during low visibility and nighttime carrier landings.

It is estimated that each F-35 Lightning pilot will conceptually require 2 1/2 to 3 1/2 helmets.  This is due to "repairs, attrition, wear and tear". Custom fitted helmet parts can not be reused. Due to the cost of the helmets, as of this writing, pilots will not be using them during training.  The helmets will only be available after the pilots are assigned to an active F-35 Lightning squadron.

Lockheed-Martin estimates that production of the F-35 Lightning, at their highly automated Fort Worth facility, can reach about 230 aircraft a year. Aircraft have not been built in the United States in such large quantities as quickly since World War II.

YouTube - F-35 Lightning Model B STOVL 

The F-35 Lightning is being produced in three variants: A conventional land based version for the USAF designated the model "A", pictured first below, a STOVL (short take-off vertical landing) version for the USMC, the Royal Air Force and the Royal Navy designated the model "B", shown in the above video, and a carrier-based version for the U. S. Navy designated the model "C" pictured second below.

In the F-35 Lightning model "B" STOVL, the weight and size of the lift fan in the aircraft takes up room that would normally be used to carry weapons and fuel. If you examine the video closely, you can see the opening for the air intake of the lift fan directly behind the cockpit.

The F-35 Lightning model "C" is a version of the basic aircraft with modifications to adapt it to aircraft carrier operations, including a larger wing. It is intended to be the U.S. Navy's first stealthy manned aircraft.

To date some 360 F-35 aircraft of all types have been produced.

F-35 Lightning model A

F-35 Lightning - model A
 F-35 Lightning model-C
 F-35 Lightning - model C
 Latest News Updates and  Milestones

April 30, 2019: In their first ever combat deployment, two U.S. F-35 Lightning model A aircraft conducted an air strike at Wadi Ashai, Iraq against a deep network of tunnels and weapons cache in the Hamrin Mountains.

April 29, 2019:  Lockheed is awarded a US$1,148,847,334 contract for "sustainment services" of F-35 Lightning aircraft with completion expected by December of 2022.

April 29, 2019:  Highlights from the U.S. Government General Accountability office report titled, "Action Needed to Improve Reliability and Prepare for Modernization Efforts",  show that the Dept. of Defense (DOD) anticipates purchasing over 2,000 F-35 Lightning aircraft at a cost of over US$270 billion.  An estimated US$10.5 billion modernization effort will begin in 2019 "without a complete business case and while still developing key technologies. This increases the risk of cost increases and delays".

"While the DOD has a plan for improving reliability and maintenance (R&M), its guidance is not in line with GAO's acquisition best practices or federal internal control standards as it does not include specific, measurable objectives, align improvement projects to meet those objectives, and prioritize funding. If the R&M requirements are not met, the F-35 Lightning may have to settle for a less reliable and more costly aircraft than originally envisioned.  Moving ahead without a business case puts F-35 Lightning modernization at risk of experiencing cost and schedule overruns similar to those experienced by the original F-35 program during its development."

April 25, 2019: A U.S. Government General Accountability Office report released today covering the period from May to November of 2018 states that “F-35 Lightning aircraft were unable to fly 30 per cent of the time because of shortages and mismatched parts”. It is yet to be a determination as to how to remedy the logistical problems and parts shortages involved with supplying parts wherever F-35 Lightning aircraft are located throughout the world. Although the majority of parts are produced in the United States, they are also made around the world by other NATO members.

April 22, 2019:  The Pentagon reports that estimated total price for research and procurement of the F-35 Lightning has increased by about 5 1/2 percent, about US$22 billion, covering "Block 4 modifications".

April 9, 2019: Today an F-35 Lightning model A of the Japan Air Self Defense Force crashed into the sea some 85 miles east of Misawa Air Base. The pilot has not been found and only small parts of the aircraft have been located.  All of Japan's F-35 aircraft have been grounded.

Feb. 28, 2019:  U.S. Navy declares that ten of their F-35 Lightning model C aircraft of Strike Fighter Squadron 147 aboard the aircraft carrier USS Carl Vinson have achieved Initial Operational Capability.

Feb. 26, 2019: Col. Paul Moga, commander of Eglin Air Force Base 33rd Fighter Squadron said, "The functionality in ALIS (Autonomic Logistics Information System) with regards to TMS (Training Management System) was such a source of frustration and a time waste to the instructor pilots and the simulator instructors and the academic instructors that we at (Air Education and Training Command) in coordination with us (at Eglin) and Luke made a call almost a year ago to stop using the program”.  Col. Moga stated that the command’s F-35 Lightning training squadrons are “not going to start using TMS again until it works.”

Feb. 25, 2019: It was reported today that Lt. Col. Kyle Shoop, commanding officer of VMFA-211,  a six aircraft F-35 Lightning model B detachment assigned to the 13th Marine Expeditionary Unit, operating aboard the amphibious assault ship Essex, said that their first combat strike was in Afghanistan in September of 2018. Their next missions were close air support and defensive counter-air for fifty days in Iraq and Syria. Shoop said, “Every day, [the pilots] were supporting over six hours of time in theater”.

Commenting on the first time F-35 Lightning model B aircraft were deployed to the Middle East, Col. Chandler Nelms, commander of the 13th Marine Expeditionary Unit, said that Members of VMFA 211 flew 1,200 combat hours over Iraq and Syria, "making up a considerable portion of the ordnance that was dropping in theater."  Nelms stated that the F-35 Lightning model B aircraft readiness "was 75 percent or better."

Feb. 15, 2019: It was announced that the F-35 Lightning will be adding or fixing a total of fifty three abilities under its Block 4 Continuous Capability Development and Delivery (C2D2) program at an estimated cost of US$16.2 billion. That includes US$10.8 billion for testing and development plus US$5.4 billion in acquisitions and improvements. The program will be implemented in four phases of six months duration each.

Some of the Block 4 upgrades include making the aircraft's Multifunction Advanced Datalink (MADL) compatible with satellite and Link 16 communications systems. In addition will be the ability to use Rover-NG systems for streaming video. The radar of the F-35 Lightning will be getting a larger aperture in order to scan wider areas with high resolution, including moving targets.

The  Autonomic Logistics Information System (ALIS) of the aircraft will receive a major redesign, new core processors, faster solid-state video memory, 4k high-resolution cockpit displays plus an Automatic Ground Collision Avoidance System.

A new advanced Electro-Optical Targeting System (EOTS) including high resolution television and short-wave infrared marker will also be part of the Block 4 improvement program.

Additional weapons carried by the F-35 Lightning are expected to include the Small Diameter Bomb II, the  Joint Standoff Weapon-C (JSOW-C), AIM-9X Block II missile, and the B-61 nuclear bomb.

It is anticipated that all Block 4 improvements will be implemented by 2023.

Feb. 11, 2019:  The U.S. Dept. of Defense is paying McKinsey & Co., Washington, DC US$15,730,560 for the F-35 Lightning "affordability campaign".  The payment "provides for maturation of the current effort through expansion and refinement of existing scope, including strategic sourcing, senior leadership team offsite, and major contract actions".  Deadline is June 2019. 

Feb. 11, 2019:  The United States Department of Defense is paying Lockheed US$90.3 million "to identify and execute cost reduction initiatives" for the F-35 Lightning.  Deadline is June of 2022.

Jan. 31, 2019:  Latest Pentagon Director of Testing and Evaluation for the F-35 Lightning report shows:

  • The service life of the U.S. Marine Corps F-35B "may be as low as 2,100 hours." Specified service life was to be 8,000 hours.
  • "Interim reliability and field maintenance metrics to meeting planned 80 % goal not being met."
  • Cybersecurity vulnerabilities "still have not been remedied."
  • F-35A air to ground weapons systems have "unacceptable" accuracy.

Nov. 16, 2018: Lockheed receives US$23 billion under low rate initial production contracts for a total of 255 F-35 Lightning aircraft. Included are 64 F-35 Lightning model A aircraft for the U.S.Air Force, 26 F-35 Lightning model B aircraft for the U.S. Marine Corps, and 16 F-35 Lightning model C aircraft for the U.S. Navy. The remaining aircraft will go to foreign customers.

Nov. 13, 2018: Initial Operational Test and Evaluation (IOT & E) for all three models of the F-35 Lightning began a seven-month period of in-depth testing today. The original evaluation date was set for the start of September. This was missed due to a late critical software update. Now all eleven months of testing are expected to be completed in nine months.

Although the F-35 Lightning can not officially “fail” the evaluation, if it does not perform to specifications, low level production runs, with existing aircraft flaws, are expected to continue. In theory, the price of the aircraft will be higher with low rate production runs. Volume discounts can be applied when more aircraft are ordered. Under United States federal law, full rate production cannot begin until the DoT &E (Director of Operational Test and Evaluation) states that the F-35 Lightning meets all current specifications.

Oct. 25, 2018:  Belgium announces the purchase of 34 F-35 Lightning model A aircraft for some US$4.14 billion with deliveries beginning in 2023.

Oct. 17, 2018:  The United Kingdom Ministry of Defence stated inspectors discovered that five of its nine F-35 Lightning model B aircraft, thus far delivered to the UK, required new fuel tubes.

Oct. 17, 2018:  Two of Australia's nine F-35 Lightning model A aircraft have been found to require new fuel tubes.

Oct. 14, 2018:  Lockheed announces that the majority of F-35 Lightning aircraft have been inspected and passed fuel tube inspection.  Those that did not pass are awaiting fuel tube replacements.

Oct. 12, 2018:  The U.S. Marine Corps announced that all of its F-35 Lightning aircraft have passed inspection of their fuel tubes and have resumed regular flight operations.

Oct. 11, 2018:  The F-35 Joint Program Office announced the grounding of all F-35 Lightning aircraft throughout the world for fuel tube inspections.

"If suspect fuel tubes are installed, the part will be removed and replaced. If known good fuel tubes are already installed, then those aircraft will be returned to flight status."

"Inspections are expected to be completed within the next 24 to 48 hours."

Sept. 29, 2018:  An F-35 Lightning model B flying out of MCAS Beauford, South Carolina was destroyed in a crash.  The cause of the crash is unknown.  The pilot is said to have ejected safely. 

Sept. 28, 2018:  The Pentagon announces latest order for F-35 Lightning aircraft totaling US$11.5 billion with deliveries beginning in 2019.  Cost for 53 F-35 Lightning aircraft model A has been reduced to US$89.2 million each.  Cost for 24 F-35 Lightning aircraft model B is now US$115.5 million each and for 14 F-35 Lightning aircraft model C reduced to US$107.7 million each.  The prices do not reflect the cost necessary to remedy the some 1,000 manufacturing deficiencies detailed by the Government Accountability Office. Deliveries will begin in 2019.  Lockheed announced that it had delivered 320 F-35 Lightning aircraft of all types to date.  The cost of fixing deficiencies on all of the aircraft delivered has not been announced. 

Sept. 27, 2018:  A U.S. Marine Corps. F-35 lightning model B, deployed from the amphibious assault ship Essex, flew the first ever combat sortie to be conducted by a U.S. F-35 Lightning aircraft.  The aircraft “flew against a fixed target in support of ground clearance operations”.  We are told that the ground forces commander considered the mission a success. 

Aug. 1, 2018: The United States Senate passes the National Defense Authorization Act that includes US$$7.6 billion for 77 F-35 Lightning aircraft. 

June 11, 2018:   The 300th F-35 Lightning was delivered today. 

June  5, 2018:  In a Government Accountability Office annual report it stated that as of January, the F-35 program had 966 “open deficiencies”.  Under the Pentagon’s current plans, at least 180 “will not be resolved before full-rate production”. 

Further stated in the report is that the F-35 building schedule is for 70 aircraft to be built in 2018. F-35 annual production output would peak at 105 aircraft in 2023 at an annual cost of $13.4 billion and stay at that rate for six years. 

The GAO stated, “In its rush to cross the finish line, the program has made some decisions that are likely to effect aircraft performance and reliability and maintainability for years to come.  That makes it imperative for the Pentagon to fix the deficiencies before a decision about production".  “If reliability targets are not met, the military services and the taxpayer will have to settle for aircraft that are less reliable, more costly, and take longer to maintain,” according to the GAO report.

According to Lockheed program officials, they expect the F-35 program “to resolve all critical deficiencies prior to entering” combat testing “with either a fix,” a service-approved work around “or a formal acceptance of the deficiency.” 

In a separate statement, the Pentagon’s office of combat testing said that as of February 2018, the number of open deficiencies had climbed to 995 with only 47 of 276 “must fix deficiencies” actually underway.

June 4, 2018:  Pratt & Whitney Military Engines, sole source of engines for all models of F-35 Lightning aircraft received a US$2 billion order for 10 engines for the U.S. Navy, 51 for the U.S. Air Force and 25 for the U.S. Marine Corps. Fifty additional engines will be sold to non-U.S. customers.

June 4, 2018:  Environmental impact studies from Florida found the F-35 Lightning aircraft produce approximately two times more noise than the twin-engine F-15 fighter aircraft, and more than three and a half times more noise than the F-16 fighter aircraft they will be replacing.

May 22, 2018:  Israel confirms it used F-35 Lightning aircraft to attack targets in Syria.

May 10, 2018:  The House Armed Services Committee Fiscal Year 2019 National Defense Authorization Act (NDAA) shows that the F-35C  while flying in stealth mode does not have the range to conduct long-range strikes without in-flight refueling. There are no stealth air tanker refueling aircraft.

May 7, 2018:  U.S. Dept. of Defence has resumed accepting F-35 deliveries after the resolution of contract disputes.

April 30, 2018:  Announcement that Lockheed Martin received a $1.4 billion contract to sustain the global F-35 enterprise for the U.S. military and international customers.  The contract provides for “air system maintenance; pilot and maintainer training; depot activation; sustaining engineering; Automatic Logistics Information System (ALIS) support, data analytics and predictive health management; and supply chain logistics” for all U.S. and international F-35s through April 30, 2019.  Of the $1.4 billion sum, about 73 percent will be paid by the U.S. Marine Corps, Air Force and Navy, while the other 27 percent will be covered by international customers.

April 11, 2018: Announcement that acceptance of F-35 deliveries halted by U.S. Dept. of Defence pending settlement of responsibility for paying costs to repair some 200 aircraft delivered by Lockheed with manufacturing deficiencies.

April 11, 2018:  Today it was announced that the F-35 Lightning had finished all of its scheduled software and developmental flight testing programs.  Next, before full scale production can commence, the aircraft must complete "Operational Test and Evaluation" (IOT&E) with testing scheduled to commence in September of 2018 and be completed by March 2019.

April 5, 2018: The U.S. Navy announced that due to delays in finishing the F-35 Lightning development period, initial operational test and evaluation (IOT&E) of their F-35 model C aircraft is not scheduled to begin until September 2018, at the earliest.

Violent vertical oscillations during F-35 Lightning model C catapult launches have been lessened to the point where they are tolerable. They were so severe that pilots could not read important instrument information while launching. It also caused most pilots to lock their harnesses during launching, making emergency switches hard to reach. It was found that tension on the bar that holds the F-35 model C nose gear immediately before launch was too strong. Reducing the tension on the bar has lessened the oscillations. F-35C pilots have also been shown ways of adjusting their harnesses so as to reach emergency switches during launches.

Overloading of F-35 Lightning model C wings when carrying AIM-9X air-to-air missiles is being addressed by fitting enhanced outer wings to the aircraft. Six F-35 model C aircraft will be used for IOT&E testing of which four have already been fitted with the enhanced outer wings. The remaining two aircraft are expected to be ready by the time testing is to start. Thereafter it is expected that two F-35 Lightning model C aircraft per month will be fitted with the enhanced outer wings.

April 4, 2018: Under the F-35 Lightning Block 4 update program, in order to meet contract specifications, in addition to the original selling prices of aircraft, Lockheed Martin will be paid a total of US$10.8 billion through 2024. Included in the update program is the "maturation of weapon capabilities".

March 15, 2018:  DOD announces F-35 Lightning total projected program cost is now US$406.1 billion.

March 7, 2018:  Lt. Gen. Steven Rudder, deputy commandant for aviation states that "the availability rate in Marine Attack Squadron 121 (based at Iwakuni, Japan) is in the mid-50 percent".

March 5, 2018:  The U.S. Air Force announced that the newest F-35 Lightning model A block 3F aircraft can now use all of their weapons throughout their entire flight envelope.

Feb. 28, 2018: Vice Adm. Mat Winter, director of the F-35 Joint Program Office announced that just a little more than half of the 280 operational F-35 aircraft can fly missions.

Problems continue to exist with the ALIS system, plus the fact that the first 100 F-35 Lightning aircraft sold still need hardware and software fixes.

Winter states: "The cost ratio we're experiencing today, if it's the same cost ratio into the future as our fleet grows from 280 aircraft to the 800-plus that we'll have by end of 2021, we will be unaffordable, in that the services' budgets will not be able to sustain that." 

It is expected that the next version of ALIS will have less problems. That, plus the fact that there is work being carried out to increase F-35 Lightning reliability and fortify maintenance should result in more aircraft becoming operational.

Feb. 2, 2018:  Lockheed Martin receives US$148 million contract to upgrade F-35's to Israel's specifications.  To date Israel has taken delivery of nine F35 Lightning model A aircraft out of 50 ordered.

Jan 23, 2018: Robert Behler, Dept. of Defense director of operational testing, reports that efforts to improve the reliability of the F-35 Lightning are "stagnant".  Aircraft have been sitting idle for over a year awaiting spare parts.  Mission availability of the 235 F-35 Lightning aircraft of all types listed as "active", as of September 2017, remains "around 50 percent, a condition that has existed with no significant improvement since October 2014, despite the increasing number of aircraft".


Prior Milestones - Oldest to Newest

April 5, 2008: The F-35 Lightning is $15 billion over budged and delayed 24 months.

Oct. 10, 2008: F-35 Lightning noise quadruple that of the F-15.

Sept. 16, 2009: "L" band radar sees through F-35 stealth.

Oct. 23, 2009: No improvements noticed in F-35 program.

Nov. 2009: Ship decks will buckle unless F-35B exhaust fixed.

Jan. 7, 2010: First testing of F-35B.

Jan. 11, 2010: U.S. government gives Lockheed US$2.8 billion to cover cost overruns.

Jan. 19, 2010: Revelation that in 2009 the F-35 Lightning was scheduled for 168 test flights; only 16 made.

Feb. 1, 2010: General in charge of the F-35 Lightning project is fired.

Feb. 1, 2010: Lockheed doesn't get US$614 million bonus.

Feb. 2, 2010: Fifth F-35 Lightning prototype test flown.

Feb. 25, 2010: Third F-35 Lightning model B starts tests.

Feb. 25, 2010: A second source of the F-35 engine "will not add to project cost" and may lower cost through competition is announced.

Feb. 25, 2010: Full F-35 production start delayed until November of 2015.

March 10, 2010: Pratt & Whitney F-35 engine costs projected to be $4.8 billion over budget.

March 11, 2010: Lockheed F-35 Lightning program $97 billion over cost and 30 months late.

March 17, 2010: F-35B has first successful hover flight.

March 18, 2010: F-35B first ever vertical landing.

April 8, 2010: First successful flight of avionics simulated weight loaded F-35.

May 20, 2010: U.S. government gives Lockheed an additional $143 million in hopes of meeting latest revised schedule.

May 20, 2010: Armed Services Committee budgets additional development funds for General Electric/Rolls Royce second engine source in 2011.

May 24, 2010: The Netherlands pulls out of the F-35 Lightning program development.

May 24, 2010: U.S. D.O.D. discloses F-35 Lightning aircraft only share about 1/4 of their parts and are actually three distinct aircraft.

June 1, 2010: Pentagon estimates F-35 Lightning program is $150.4 billion over budget, 48 months late.

June 7, 2010: First F-35 model C flown.

June 15, 2010: First Mach 1+ flight of F-35 model B during which parts of aircraft fall off and excessive vibration experienced.

Jan. 18, 2011: Pentagon reveals F-35 Lightning unstable during low and transsonic speed flight tests; engine fails full power performance tests; avionics do not meet specifications; parts failing at high rates.

Feb. 4, 2011: The Pentagon announces that the F-35 Lightning program needs $4.6 billion dollars more in 2012 to address engine problems and necessary upgrades.

Feb. 10, 2011: Announcement that Congress "saves" U.S. taxpayers $450 million by terminating the competitive engine program by General Electric that may have helped keep costs down. The F-35 Lightning program now depends only on the Pratt & Whitney engine, that thus far has not performed to specifications and is billions over budget, that will have no competition.

March 11, 2011: F-35 Lightning flight tests stopped due to leaking oil and on board power failures.

March 15, 2011: GAO announces that F-35 computer programs are more than three years behind development schedule.

March 18, 2011: Pentagon says that the anticipated price tag to manufacture and support the F-35 Lightning is "still unacceptable". Meanwhile the USAF and USN tell Congress that costs are "credible".

March 22, 2011: USAF admits before Congress that deployment of the F-35 Lightning will again be delayed, this time at least another two years.

March 24, 2011: Turkey cancels plans to purchase 100 F-35 Lightning aircraft (see Jan. 6, 2012).

May 5, 2011: First refueling of the F-35 by an operational U.S.A.F. tanker aircraft.

Nov. 4, 2011: F-35 achieves a maximum speed of 1,062.6 mph.

Nov. 9, 2011: Pratt & Whitney says their engine in the F-35 Lightning model B has been tested successfully for short take off and landing from the deck of a ship at sea.

Dec. 14, 2011: Pentagon F-35 Lightning report shows:

Pilot's helmet display has night vision and blurring problems.

Fuel dump leaves deposits on aircraft.

Arresting hook on the F-35 does not work. The problem appears to be the short distance (about 10 feet less than other jet carrier aircraft) between the landing gear and tail hook. The hook apparently skips across the arresting cables on the carrier's deck without catching them.

The U.S. Navy says it will be too costly to raise the position of the arresting cables on its carriers, requiring changes to the tail hook system of the F-35 Lightning model C. Thus far higher tension dampeners have been installed to make the tail hook skip less, and the tail hook has been reshaped.

Premature failure of airframe components.

Premature electrical systems failures including redundant systems, pilot oxygen, and cockpit pressurization.

Severe shaking while maneuvering at supersonic speeds.

Overheating of electrical systems in primary displays.

Inability to fly aircraft under loads to fully test thermal management.

Inability to fly air-to-air or air-to-ground test flights.

Fuel system susceptible to fires.

Aircraft easily damaged by lightning strikes resulting in directive not to fly within 25 miles of thunder storms.

Frequent failure of integrated power pack system.

Range and maneuverability affected much more than anticipated as aircraft payloads increase.

F-35 Lightning software development is now five years behind schedule.

Overall F-35 Lightning program costs have increased by about US$3 billion to now total about US$385 billion since last estimate.

Lockheed responded to the Pentagon report by stating that they have exceeded their 2011 development goals.

Dec. 20, 2011: Japan announces that it may acquire up to 43 F-35 Lightning aircraft while negotiating the purchase of six of the aircraft.

Dec, 22, 2011: Robbin Laird, F-35 Lightning program supporter, wrote that Japan's decision to purchase the F-35 is an excellent decision. According to Laird, the F-35 will be equipped with the latest systems. With other aircraft those systems would need to be added. Laird further states that it is intended that anti-ballistic missile systems, such as the Aegis, used by the U.S. Navy, will be able to link to systems on the F-35 for over-the-horizon guidance, once developed. The sensor systems being developed for the F-35 are "unique" and "world-class" for the delivery of air to air and air to ground ordnance. If other U.S. allies in the area all purchase the F-35, Japan's aircraft will more easily be able to fly joint missions with them.

Jan. 6, 2012: Turkey announces they will conduct talks with Lockheed regarding the purchase of two F-35 Lightning aircraft. On March 21, 2011 Turkey canceled their plans to purchase 100 of the aircraft. At this time it is unclear if they are considering revising their decision.

Jan. 18, 2012: Tom Burbage, F-35 Lightning program manager says, "Based on the original spec, all three of the airplanes are challenged by that spec. The cross-sectional area of the airplane with the internal weapons bays is quite a bit bigger than the airplanes we're replacing." The sharp rise in wave drag at speeds between Mach 0.8 and Mach 1.2 is one of the most challenging areas for engineers to conquer. And the F-35's relatively large cross-sectional area means, that as a simple matter of physics, the jet can't quite match its predecessors. "We're dealing with the laws of physics. You have an airplane that's a certain size, you have a wing that's a certain size, you have an engine that's a certain size, and that basically determines your acceleration characteristics," Burbage said. "I think the biggest question is: are the acceleration characteristics of the airplane operationally suitable?"

Jan. 19, 2012: Lockheed announces that they will start testing of a new fuel dump system that doesn't deposit fuel on the aircraft in April of 2012.

Jan. 20, 2012: Pentagon says all 63 F-35 Lightning aircraft delivered to date need major air frame and electronics upgrades to become operational.

Feb. 15, 2012: Pentagon delays purchases of 179 F-35 Lightning aircraft through 2016 to decrease number of aircraft delivered needing air frame and electronic upgrades.

Feb. 16, 2012: Italy announces reduction in F-35 purchases from 131 to 90 aircraft.

Feb. 17, 2012: Lockheed says cost of the F-35 Lightning will be increased an unspecified amount, due to purchase delays and reductions.

March 20, 2012: U.S. GAO announces first 63 F-35 airplanes cost US$1 billion more than anticipated. All of the aircraft will need major rebuilding before being able to fly combat missions. The cost for rebuilding has not been included in the GAO report.

March 29, 2012: The Pentagon announces the latest F-35 Lightning program costs increased another US$16.3 billion and is now at US$395.6 billion.

Oct. 18, 2012: In a press release today it was announced that the F-35 tested its ability to drop an approximately 2,000 lb. bomb from its internal bomb bay. The drop was accomplished as intended.

Dec. 4, 2012: Lockheed announces combined total flight hours of all F-35 test aircraft has exceeded 5,000.

Dec. 12, 2012: Canada cancels plans to order 65 F-35 Lightning aircraft.

Dec. 14, 2012: U.S. orders additional 32 F-35 aircraft in advance of 2013 military budget reductions.

Jan. 28, 2013: Pentagon reveals that due to additional software development delays it will be at least 2017 before any F-35 is able to fly combat missions.

May 23, 2013: The Pentagon announces that estimated costs for the development and production of the F-35 Lightning has decreased by 1.1% for savings of about US$4.5 billion under previous estimates and a new total cost of US$391.2 billion.

May 29, 2013: U.S. Navy announces numerous modifications needed for their LHD/LHA ships to accommodate the F-35 Lightning model B STOVL aircraft due to its intense exhaust temperature. Moving parts and/or additional shielding is required to keep decks from corroding and buckling, plus damage to antennas, fuel stations, missile launchers, netting, rafts, railing, and ship weapons systems. The nozzles of the F-35 model B are undergoing a redesign to spread their output in order to minimize the concentration of exhaust gasses, thus limiting the damage they can cause.

May 30, 2013: The F-35 Lightning model B is not able to carry a center gun pod. The U.S. Navy admitted that they do not yet have a mission for it due to none of its current weapons being suitable for use "against quick moving targets or a situation in which the risk of collateral damage is high".

The U.S. Navy had decreased F-35 model B and C production rate by about one-fifth, and is planning on using their 134 Harrier Jump Jets, which have received continuing upgrades, through at least 2027.

As of this writing it is unclear if the additional expenses necessary to modify U.S. Navy ships will exceed the savings claimed in prior statements.

May 31, 2013: The Pentagon announces that at least 10 F-35 model B aircraft for the U.S. Marine Corps will achieve an Initial Operational Capability (IOC) by December 2015; at least 12 F-35 model A aircraft for the U.S.A.F. will achieve an initial operational capability by December 2016; and the U.S. Navy will achieve an initial operational capability for about 12 F-35 model C aircraft by February 2019.

June 10, 2013: U.S. Dept. of Defense admits to more unspecified engine testing and development delays, gives Pratt & Whitney $648.9 million more to cover expenses, and for two more test engines.

June 19, 2013: The Defense Department's chief weapons-tester, Michael Gilmore, reported to the Senate Defense Appropriations Subcommittee that radar and electro-optical system problems are further delaying weapons integration in the F-35 Lightning. Buffet and transsonic wing drop "continue to be a concern to achieving operational combat capability."

Software delays caused by continuing problems with the Helmet Mounted Display System, plus additional tests necessary to insure that program changes made to correct past issues will not interfere with existing software, have added 366 test points to 2013 goals.

About 65% of in-flight testing of the latest non-combat software is yet to be accomplished.

U.S.M.C. F-35 Lightning model B Block 2B software was due for delivery during August 2013, but has been delayed an additional eight months.

Final testing must be completed for operational evaluation due in 2015 in order for the Marine IOC scheduled for completion by December of 2015.

According to Gilmore, even full Block 2B aircraft will "likely need significant support from other (fighters) . . . unless air superiority is somehow otherwise assured and the threat is cooperative."

"The most significant source of uncertainty" regarding F-35 combat capability in 2018, is that the program has to deliver an operational Block 3i while concurrently developing Block 3F, which is intended to meet the key performance parameters "set in 2001".

In the report it shows that the Helmet Mounted Display System has less jitter, but now has "swimming of the symbology". Also, to compensate for light leakage or "green glow" pilots must do "fine-tuning adjustments" of display brightness while flying. RCESA is the manufacturer of the helmets. It is a combined venture of Rockwell Collins in the U.S.A. and Elbit of Israel. The latest cost estimate of a helmet is over US$500,000. It had been reported that BAE was also working on a helmet to solve its issues. It was reported that the BAE helmet price was up to US$150,000 less each than the RCESA helmets. It now appears that RCESA will be the only source for the helmets.

Gilmore reports, "The final Block 3F weapon integration tests are likely to be completed in late 2017, instead of 2016. This will make beginning operational testing of Block 3F in January 2018 a challenge."

Buffet and transsonic roll-off of the F-35 Lightning have not been resolved. Gilmore reports that the program has now reached a limit on what can be done with control laws. More changes would affect maneuvering or tax the airframe.

Lightning-tolerance testing is yet to be completed. The F-35's airframe will have to be inspected after known lightning strikes. According to Gilmore, the F-35 Lightning does not use lightning-tolerant fasteners. Conventional fasteners were selected to save weight.

Gilmore reports that the F-35 Lightning model B lift-fan system "might fail catastrophically before the pilot can react" during transition to vertical landing due to lack of a working detection system. Lockheed-Martin says "in the remote chance of a failure, the pilot would auto-eject."

Nov. 27, 2013:  The F-35 is even more vulnerable to lightning and anti aircraft fire than previously reported.

Maximum g forces for continuous turns are now projected to be 4.6 g for the F-35 model A, 4.5 g for the F-35 model B, and 5.0 g for the F-35 model C. Most fighter aircraft are capable of 9.0 g continuous turns.

The F-35 model C takes 43 seconds longer than an F-16 to accelerate from Mach 0.8 to Mach 1.2, the F-35 model B takes 16 seconds longer, and the F-35 model A takes 8 seconds longer.

According to Gilmore the F-35 model B and F-35 model C use almost all of their internal fuel before being able to achieve their maximum speed of Mach 1.6. We have been unable to find mention of the F-35 model A.

Test pilots said that poor visibility from the F-35 Lightning cockpit will get them "consistently shot down in combat."

The F-35 systems lack complete software in order that pilots can be trained safely.

Ejection seats are subject to numerous failures.

Avionics are unreliable and fail to respond to inputs.

Radar may not work properly, if at all.

Heat on the skin of the F-35 Lightning, generated by supersonic flight speeds, causes the stealth paint covering of the aircraft to wear out prematurely.

Engines that are supposed to be replaced in two hours have thus far taken about 52 hours to be replaced.

Tools assigned to maintain the aircraft fail to provide proper functionality.

Dec. 4, 2013: Elgin Air Force Base announced that on that date a U.S.A.F. F-35 model A flew 10 flights, a USMC F-35 modl B flew 32 flights, and a U.S.N. F-35 model C flew three flights. It is the most amount of total flights for F-35 Lightning aircraft ever in a single day. The duration of each flight was not announced, nor was the collective total time of the flights.

Dec. 19, 2013: Lockheed announced that the cost of the F-35 model A, USAF version, will be reduced to US$85 million by 2019, including its engine and weapons systems.

Jan. 31, 2014: The U.S. Pentagon says that the initial operational capability for ten USMC F-35 model B aircraft will most likely be delayed from December of 2015 to January 2017 (see May 31, 2013 above).

The F-35 model B has continuing reliability and maintenance issues.

The problem with fuel igniting if the F-35 is hit by a missile remains outstanding.

The AIM-120 Advanced Medium-Range Air-to-Air Missile system is plagued by unknown computer programming errors.

The missile threat warning system interprets flares disbursed by the F-35 as incoming threats.

The F-35 Lightning model B is extremely vulnerable to small arms fire that can disable its vertical landing system.

F-35 Lightning aircraft are leaving the assembly line with valves reversed and spots in their stealth covering.

Two thirds of all F-35 Lightning aircraft currently deployed are not airworthy.

Aircraft inertial navigation systems do not function.

Lt. Gen. Chris Bogdan, in charge of the F-35 Lightning program for the U.S. government responded, saying that he feels that the F-35 model B aircraft will be ready without any additional delays. He added that program risks are "understood and manageable."

In the U.S. 2015 budget, the F-35 Lightning model A for the U.S.A.F. will cut four aircraft, from 30 to 26.

The U.S.M.C. will stand fast with 69 F-35 model B aircraft ordered.

The U.S. Navy will cut 29 F-35 model C aircraft, from 49 to 20.

Feb. 2, 2014: U.S.A.F. Lieutenant General Charles Davis, former F-35 Lightning program Executive Officer, states that the JSF program "was doomed the day the contract was signed".

Feb. 14, 2014: U.S. Air Combat Command chief Gen. Mike Hostage states, "If I do not keep that F-22 fleet viable, the F-35 fleet frankly will be irrelevant. The F-35 is not built as an air superiority platform. It needs the F-22."

March 24, 2014: The U.S. Government Accountability Office (GAO) released a report stating a need by the U.S. Department of Defense to "drastically increase spending in the next five years" on the F-35 Lightning program, particularly with regard to mission systems software. If they do not, it is unlikely that the program can meet current schedules.

The additional expenses involve the inability to accomplish software goals, especially in regard to retesting numerous sequences of program copies.

Should additional spending not be approved, delays of this importance "will likely limit the war fighting capabilities" of the F-35 Lightning.

Due to ongoing testing, the extent of the diminished capabilities is still unknown. However, delays may further increase program costs.

The DOD will be redetermining program benchmarks and, as recommended by the GAO, reporting realistic goals to the U.S. Air Force, U.S. Navy, and Congress by July of 2015.

April 21, 2014 Lockheed announces another price increase in development costs of the F-35 by US$7.4 billion.

April 21, 2014 Lockheed announces that they have re-calculated lifetime cost of aircraft and have reduced the amount by US$89.4 billion. Lockheed says the new amount will more than offset the price increases in development costs.

We understand that the basis of the new lower operating cost calculation is lower labor rates. The Dept. of Defense now says that they will save money by having military personnel do the bulk of F-35 Lightning repair and maintenance work rather than independent contractors as originally announced. This flies contrary to what the DOD has been saying to justify the increasing amount of non-military contractors taking over jobs that were formerly performed by the military as a cost saving measure. One of the reasons that countries have agreed to purchase the F-35 Lightning is that private companies were supposed to benefit from doing maintenance and repair work on the aircraft.

The DOD also announced that only ten percent of the missions flown by the Marine F-35 Lightning B aircraft will be in stealth configuration to save money. Presumably the surface of the aircraft will not have to be perfectly maintained to avoid radar detection. Maintaining the stealth covering of aircraft is a large cost factor in their operation and maintenance.

April 23, 2014: Australia will buy 58 F-35 Lightning model A aircraft for US$12.4 billion.

April 25, 2014: Lockheed announced that test hours flown by all of its F-35 aircraft have exceed 15,000.

April 25, 2014: South Korea may buy 40 F-35 Lightning aircraft for US$6.8 billion. They may sign a contract before the end of 2014.

May 6, 2014: Turkey bought two F-35 Lightning aircraft for US$320 million. They may order 98 more by 2016.

May 10, 2014: U.S.A.F. Col. Michael W. Pietrucha states, "Viable alternatives to the F-35 exist if we have the courage to examine them."

May 29, 2014: F-35 Lightning model A flies with Block 3i hardware and software for almost two hours.

F-35 Lightning -firing-missile

F-35 Lightning - Launching Missile

May 30, 2014: F-35 Lightning model B launches two AIM-120 air-to-air missiles.

June 2, 2014: F-35 Lightning model C simulates aircraft carrier landings on a runway at NAS Patuxent River, MD.

June 6, 2014:  U.S. Air Combat Command chief Gen. Mike Hostage in an interview says, "I’m going to have some F-35's doing air superiority, some doing those early phases of persistent attack, opening the holes, and again, the F-35 is not compelling unless it’s there in numbers." Furthermore, "Because it can’t turn and run away, it’s got to have support from other F-35's. So I’m going to need eight F-35's to go after a target that I might only need two Raptors to go after. But the F-35's can be equally or more effective against that site than the Raptor can because of the synergistic effects of the platform.” He goes on to say, "The F-35′s cross section is much smaller than the F-22′s. "The F-35 doesn’t have the altitude, doesn’t have the speed, but it can beat the F-22 in stealth."

June 13, 2014: The British government announces that they will be spending about the equivalent of US$12.6 million to build three special F-35 Lightning model B landing pads at RAF Marham to withstand high exhaust temperatures.

June 23, 2014: F-35 model A engine fire during takeoff destroys aircraft while pilot is unharmed. All F-35 Lightning aircraft are grounded through July 15, 2014.

July 14, 2014: F-35 Lightning model B does not make scheduled appearance at 2014 Farnborough Air Show. F-35 testing will be extremely limited until cause and cure of engine fire are found.

Sept. 16, 2014: U.S.A.F. Lt. Col. Dan Ward writes about the F-35 Lightning program:  "Complexity, cost, and development timeline all pointed to an ill-advisedly large, pricey, and slow effort that was immediately on track to cost more, take longer, and deliver less than promised."

Sept. 22, 2014: The U.S. Government Accountability Office says that long term costs of the F-35 Lightning may "not be affordable". The GAO states that the annual maintenance expenses for the majority of aircraft that the F-35 is supposed to replace, those being the Harrier, F-15, F-16, and F-18, amounted to US$11 billion in 2010. The GAO estimated that to maintain the same number of replacement F-35 aircraft it would cost US$19.9 billion annually in 2012 dollars.

It is estimated that the cost to fly an F-35 Lightning production aircraft for an hour will be around $77,000. In 2012 the Harrier cost per hour of flight was $18,926, F-15 $41,921, F-16 $22,514, the A-10 $17,716, and F-18 $32,044. The costs will probably grow higher as the aircraft age.

A large part of the cost difference is the mean time between critical failures of legacy aircraft and the F-35 Lightning. In 2014 the F-35 was averaging 42 percent below its requirement anticipated at program maturity. The GAO also said that the time necessary to repair F-35 aircraft is growing longer.

Sept. 25, 2014: South Korea orders 40 F-35 Lightning model B aircraft at a cost of around US$177.5 million each for deliveries from 2018 to 2024.

Nov. 3, 2014: U.S. Navy F-35 model C aircraft makes first successful arresting hook landing aboard carrier at sea.

Nov. 4, 2014: It was announced today that a joint investigation by the U.S. Dept. of Defense and Pratt & Whitney to find the cause of the engine fire that destroyed the F-35 Lightning model A aircraft on June 23, 2014 has concluded that, "a hard rub between the rotor 3 and the polyimide stationary seal on stator 2 led to excessive heating and fracturing of the rotor in the fan section of the engine."

Nov. 12, 2014: The U.S. Naval Air Forces Public Affairs Office reported that the two F-35 Lightning model C aircraft undergoing at-sea trials aboard the USS Nimitz aircraft carrier have completed a total of 57 successful landings without a single failure to catch an arresting cable.

The U.K. has committed to the purchase of four F-35 model B aircraft of a potential 14 aircraft purchase, less engines, but including Lockheed "support costs", for about US$3.94 billion. The U.K. hopes to eventually have 48 F-35 model B aircraft ready for combat by the mid 2020's.

Nov. 24, 2014: Israel rejects buying an additional 31 F-35 Lightning aircraft and cuts the second batch of F-35's to 13. A senior Israeli official said, "For maintaining stealthiness, this aircraft has compromised maneuverability, shorter operational range and significantly less payload capability. We shouldn’t be buying so many of them when it is unclear whether the stealth is effective, or there is a countermeasure that would negate it. There are vast gaps in performance between the F-35 and fourth-generation fighters."

Nov. 27, 2014: Dummy British ASRAAM air to air missiles, duplicating the weight and shape of the actual missiles, are fitted to the outboard pylons of the F-35 model B to test the aircraft's abilities to carry the weapons. It is anticipated that actual weapons will be tested and fired in early 2015. The ASRAAM is a short range missile using infra-red homing.

Dec. 4, 2014: The U.S. Pentagon announced that it is possible that the air-to-air missiles arming the F-35 Lightning, such as the AIM 120, are susceptible to jamming by aircraft that they may face in combat. Also, Russia has developed missiles with a longer range that are far less susceptible to jamming, according to U.S.A.F. officials. The officials believe that it is possible that "some" missiles would avoid jamming, but that the F-35 just doesn't carry enough missiles to be effective, especially while flying in stealth with only internally carried missiles. At present the F-35 Lightning only carries four air to air missiles internally, and it is hoped that it can be increased to a total of six missiles. Air Force intelligence chief Lt. Gen. Dave Deptula, retired, said it’s “critical” that the F-35 moves “air-to-air weapons into a future where they can effectively deal with adversary electronic attack."

Dec. 5, 2014: USAF reveals that the F-35 can "shut down" when fuel gets too hot. Fuel trucks for F-35 aircraft are being painted white as a temporary solution

Dec. 11, 2014 A Canadian government report states that the F-35 Lightning "has no clear edge" over any other currently produced aircraft being considered for future purchase by Canada. However, were Canada in the exceptionally unlikely position of having to go to war with another country, if the F-35 were to perform as advertised by Lockheed, it could have an advantage.

Dec. 23, 2014 A USAF F-35 Lightning program official says that F-35 air-to-ground sensors are over ten years old and obsolete. The F-35 also can not carry the infra red marker used by today's aircraft to illuminate targets. The compromise was made to fit into the stealth aircraft design. Currently flying aircraft can carry pods that have higher definition images which can be seen at greater distances than those of the F-35. The F-35 does not have he ability to send the images in real time to ground troops, as do currently operating aircraft. Eventually more funds will have to be appropriated to bring the F-35 up to date.

Jan. 6, 2015 In response to recent news stories regarding the F-35 Lightning gun not being operational until 2019, Lockheed spokesman Mike Rein said, "The requirement for the gun was established in 2005. It’s always been in the block 3F weapons to be delivered in 2017, not 2019." Further, the services know "that when they declare IOC (initial operating capability) they aren’t going to have all their weapons on their airplane at that time. Some of the additional capabilities for consideration include items such as Higher Definition Video, longer range target detection and identification, Video Data Link, and Infrared (IR) Marker and Pointer. All of the services and international partners are aware of the block upgrade plan and have endorsed its timeline."

June 18, 2015: The Air Logistics Complex, Ogden, Utah, announced the completion of 24,000 hours in modifications to two F-35 Lightning model B aircraft so they could be made ready for USMC Initial Operating Capability (IOC).

July 31, 2015: The U. S. Marine Corps declares Initial Operational Capability (IOC) for the F-35 Lightning model B.

March 4, 2016:  First successful bomb drop from F-35 Lightning.

April 14, 2016: The U.S. Government Accountability Office (GAO) reports their concern that a failure in the F-35 Lightning Autonomic Logistics Information System (ALIS) could ground the entire fleet because it lacked a back-up for processing data.

Aug. 2, 2016: The U.S. Air Force declares initial Operating Capability (IOC) for the F-35 Lightning model A.

Aug. 26, 2016: Luke Air Force Base takes delivery of its 100th F-35 Lightning model A.

Oct. 27, 2016: An F-35 Lightning model B has a weapons bay fire during flight. The pilot was able to safely land the aircraft. Its cause was traced to a broken bracket leading to rubbing the covering off electrical wiring. The resultant electrical short ignited fluid leaking from a worn hydraulic line.

July 25, 2017: Lockheed Martin announces that the combined flight hours for all variants of the F-35 Lightning have reached 100,000.

Oct 26, 2017 - U.S. GAO announces that "DOD's capabilities to repair F-35 parts at military depots are six years behind schedule, which has resulted in average part repair times of 172 days—twice the program's objective.".

Dec. 5, 2017:  Israeli Air Force announces that their F-35 Lightning model A "Adir" achieved initial operating capability .

Dec. 18, 2017: Lockheed Martin announced that it delivered a total of 66 F-35 Lightning aircraft of all types during 2017. That met its projected delivery goal for the year.

Jan 23, 2018: Robert Behler, Dept. of Defense director of operational testing, reports that efforts to improve the reliability of the F-35 Lightning are "stagnant".  Aircraft have been sitting idle for over a year awaiting spare parts.  Mission availability of the 235 F-35 Lightning aircraft of all types listed as "active", as of September 2017, remains "around 50 percent, a condition that has existed with no significant improvement since October 2014, despite the increasing number of aircraft".


 RC F-35 Lightning

Freewing's RC F-35 Lightning is PNP with a 31 1/2 in. wingspan and 45 in. length.  Included is 360 degree thrust vectoring, retracts, a 2839 - 3,000 kV motor turning a 70 mm EDF unit.  It needs your radio, a 2200 mAh Li Po flight battery and charger.