...A helicopter with...

One set of rotors Skid rails (even if with wheels)
Wheels (fixed or retractable)
Two separate sets of rotors

























...A helicopter with skid rails (even if with wheels)...

No tail-rotor
Hook-like frame around tail rotor
Tail-rotor mounted inside circular housing
Two/three seater (inc. military)
Tail-plane with fins
Tail-rotor located on top of tail
Tail-rotor located at fuselage level

























...A helicopter with wheels (fixed or retractable)...

Hook-like frame around tail rotor
Tail rotor mounted inside circular housing
Twin rotor-set on single shaft
Crane design
Tail-plane with fins
Tail-rotor located at fuselage level
Tail-rotor located on (or near) top of tail Tail-plane on both sides
Tail-plane on starboard side only
Tail-plane on port side only

Helicopter, one rotor, skid rail (even if with wheels), no tail-rotor

One tail
	Kaman K-Max

No tail
	McDonnell Douglas MD Explorer


Helicopter, one rotor, skid rail (even if with wheels), hook-like frame around tail rotor

Engine mounted above boom
	Aerospatiale Alouette II

Rear fin
	Bell 47

Two-seater
	Brantly B-2

Four-seater
	Robinson R44


Helicopter, one rotor, skid rail (even if with wheels), tail rotor mounted inside circular housing

Fins on tailplane
	Aerospatiale SA.341/342 Gazelle

None of the above features
	Guimbal G2 Cabri


Helicopter, one rotor, skid rail (even if with wheels), two/three seater (inc. military)

Tail below fuselage boom level, engine uncovered
	Silvercraft SH-4

Tail below fuselage boom level
	Enstrom 280 Shark

Engine uncovered, rear fin
	Hughes/Schweizer 269/300/300C/TH-55A Osage

Transmission to tail-rotor jointed along fuselage boom
	Rogerson Hiller UH-12/260/H-23 Raven

Armed attack helicopter
	Bell AH-1 HueyCobra/SeaCobra

None of the above features
	Robinson R22 Alpha


Helicopter, one rotor, skid rail (even if with wheels), tail-plane with fins

Engine uncovered
	Westland Scout

Tail-plane above tail rotor
	McDonnell Douglas 500

Sponsons on each side of fuselage
	Bell 222UT

Tail-rotor on top of tail
	MBB-Kawasaki Bk.117
	MBB BO 105
	MBB BO EC 135

None of the above features
	Bell 206L LongRanger III
	Bell 206L-4 LongRanger


Helicopter, one rotor, skid rail (even if with wheels), tail-rotor located on top of tail

(Half) tail-plane on top of tail
	Westland Lynx (AH.1)

Tail-rotor on starboard side
	Bell 212/412/212ASW
	Bell 214A/214B/214ST

Sliding cabin door, with one window
	Bell 204/UH-1 Iroquois

Sliding cabin door, with two windows
	Bell 205/UH-1 Iroquois/205A-1

None of the above features
	Rogerson RH-1100


Helicopter, one rotor, skid rail (even if with wheels), tail-rotor located at fuselage level

Tail-rotor on port side
	Bell 206 JetRanger/OH-58 kiowa
	Bell 206L Long Ranger

Tail-rotor on starboard side, tailplane on top of tail
	Mil Mi-34 'Hermit'

Tail-rotor on starboard side
	Aerospatiale AS.350/355 Ecureuil/AStar/TwinStar


Helicopter, one rotor, wheels (fixed or retractable), hook-like frame around tail rotor

Engine uncovered
	Aerospatiale Alouette III

Engine covered
	Brantly-Hynes 305


Helicopter, one rotor, wheels (fixed or retractable), tail rotor mounted inside circular housing

Tandem two-seater, stealth design
	Boeing/Sikorsky RAH-66 Commanche

Fixed wheel
	Aerospatiale SA.360/361H Dauphin

Retractable wheels
	Aerospatiale SA.365 Dauphin 2
	Aerospatiale AS.565 Panther


Helicopter, one rotor, wheels (fixed or retractable), twin rotor-set on single shaft

Two tails below fuselage boom level
	Kamov Ka-26/126 'Hoodlum'

Two tails
	Kamov Ka-27 'Helix'
	Kamov Ka-29/31

Three tails
	Kamov Ka-25 'Hormone'

One tail
	Kamov Ka-50 Werewolf (Hokum)


Helicopter, one rotor, wheels (fixed or retractable), crane design

One wheel strut each side
	Sikorsky S-64 Skycrane/CH-54 Tarhe

Two wheel struts each side
	Mil Mi-10/K 'Harke'


Helicopter, one rotor, wheels (fixed or retractable), tail-plane with fins

tail-rotor located at fuselage level
	Bell 222

tail-rotor located on top of tail
	Westland 30


Helicopter, one rotor, wheels (fixed or retractable), tail-rotor located at fuselage level

	Agusta A109


Helicopter, one rotor, wheels (fixed or retractable), tail-rotor located on (or near) top of tail, tail-plane on both sides

Engine uncovered
	Westland Wasp

Tandem two-seater attack helicopter, fins on tailplane
	Eurocopter Tiger

Tandem two-seater attack helicopter
	McDonnell Douglas AH-64A Apache
	Agusta A129 Mangusta

Cockpit on upper deck
	Mil Mi-4 'Hound'
	Sikorsky S-55/H-19/S-55T
	Sikorsky S-58/S-58T/CH-34 Choctaw
	Westland Wessex

High-mounted wings, two cockpits
	Mil Mi-24 'Hind D'

High-mounted wings
	Mil Mi-6 'Hook'

Fin extension on lower half of tail
	Kaman H-2 Seasprite

Sponsons on each side of fuselage
	EHI EH 101
	Mil Mi-14 'Haze'

Tail-plane hinged on lower tail
	Sikorsky S-70/UH-60A Black Hawk
	Sikorsky SH-60B Seahawk

Eight-bladed rotor
	Mil Mi-26 'Halo'

None of the above features
	Mil Mi-2 'Hoplite'
	Mil Mi-8/Mi-17 'Hip'
	Sikorsky S-76 Spirit
	PZL Swidnik W-3 Sokol (Falcon)


Helicopter, one rotor, wheels (fixed or retractable), tail-rotor located on (or near) top of tail, tail-plane on starboard side only

Tail and tail-rotor tilted (40 degrees to port side)
	Sikorsky CH-53E Super Stallion

Large engine housings each side of upper fuselage
	Sikorsky S-56/H-37 Mojave

Side floats with struts
	Aerospatiale SA.321F Super Frelon
	Sikorsky S-61L/N
	Sikorsky S-62
	Sikorsky SH-3/S-61
	Westland Sea King/Commando

Side floats without struts
	Sikorsky S-61R/CH-3E/HH-3F Pelican
	Sikorsky S-65A/CH-53 Sea Stallion
	NH NH90

No side floats
	Westland Lynx HAS.2


Helicopter, one rotor, wheels (fixed or retractable), tail-rotor located on (or near) top of tail, tail-plane on port side only

Tandem two-seater
	Atlas CSH-2 Rooivalk
	Mil Mi-28 'Havoc'

Fuselage fin below tail
	Aerospatiale SA.332 Super Puma

No fin below tail
	Aerospatiale/Westland SA.330 Puma


Helicopter, two separate sets of rotors

Rear side floats
	Boeing-Vertol H-46 Sea Knight/107

No side floats
	Boeing-Vertol CH-47 Chinook