Most safe "Century Series" aircraft produced, and one of the aircraft with the best safety records in the history of the USAF:  F-111

Most expensive U.S. military aircraft project in the history of the world: F-35

One of the most reliable transport aircraft ever produced:  C-119 Flying Boxcar

Arguably the world's most versatile turboprop military transport aircraft:  A400M

Most easy two seat aircraft to fly:  Ercoupe

Most heavily armed bomber of World War II: Bristol Beaufighter

Has a continuous roll rate of about 500 degrees per second, said to be the most of any aircraft of its kind currently flying in the world:  Giles 202

Had the most U.S. unlimited aerobatic competition wins:  Pitts

Most "green" airliner:  787 

Most expensive mass produced rotor aircraft:  V-22 Osprey

Most expensive aircraft ever produced:  B-2 Spirit

Most expensive civil aviation aircraft:  A380

Most take off weight world record (MTOW) for a twin engine aircraft:  777-300ER

Most sold single engine aircraft:  SR 22

Most widely used military transport in the West: C-130

Most ugly mass-produced aircraft:  Barracuda

Most expensive cancelled U. S. military helicopter project:  RAH-66

Most efficient power-lift system ever developed incorporated on this aircraft:  YC-14

Most low attrition rate of any World War II front line aircraft:  B-26 Marauder

Most successful homebuilt canards:  VariEze and Long-EZ

Most distance for combat mission:  Eighth AF B-52 bombers from Barksdale AFB, Louisiana to Kuwait during Operation Desert Storm.

Most produced aircraft of its class:  Boeing 737

Most famous Japanese WW II bomber:  G4M Betty

Most famous British WW II bomber: Lancaster

Most famous U.S. WW II bomber:  B-17

Most widely used U.S. twin engine transport in the Pacific theatre during WW II:  C-46

Most built U.S. trainer aircraft:  AT-6

Most built turboprop airline in the West:  F-27

Most produced aircraft in history: IL-2

Most popular advanced jet trainer aircraft of today: L-39

Most famous and most built Japanese WW II fighter: A6M Zero

Most effective British WW II fighter bomber: Typhoon

Most long serving British jet fighter: Hunter

Holds the Guinness World record for longest production run, most of any type of aircraft in the world:  An-2

Had a production run of about 25 years, the most of any tactical aircraft in aviation history:  A-4

Most heavily armed current aircraft: AC-130

Most victories over Japanese aircraft in WW II: F6F

Most victories of any U.S. World War II fighter aircraft: P-38

Most luxurious production passenger plane in the world: China Clipper

Most advanced Chinese fighter: J-10

Most advanced Swedish fighter: JAS-39

Most advanced French fighter: Rafale

One of the world's most advanced multi-role fighter aircraft: Eurofighter

Most advanced Russian 5th Generation plus fighter: Sukhoi Su-57

Most advanced Russian attack helicopter:  Ka-50

Most produced U.S. World War II light bomber: A-20

Most produced bomber of all time: B-24

Most produced Japanese Army World War II fighter:  Ki-43

Most produced current Western fighter: F-16

Most produced overall jet fighter: MiG-15

Most produced ever supersonic jet fighter: MiG-21

Most produced fighter plane of all time: Bf/Me 109

Most produced ever flying boat: PBY Catalina

Most produced biplane ever with over 40,000 built: Polikarpov Po-2

Most German troops and supplies during World War II transported by this plane:  Ju 52

Most effective Luftwaffe World War II dive bomber: Ju 87

Most versatile Axis WWII bomber: Ju 88

Most flight time without landing, with refueling, 1,558 hours, 19 minutes: Cessna 172

Most flight time without refueling or landing, 9 days, 3 hrs, 44 min, around the world: Rutan Voyager

Most quiet helicopter in the world: EC 135

Most quiet transoceanic aircraft currently in service:  A380

Most quiet aircraft in the world:  YO-3A

Most loud aircraft in the world:  XF-84H