Boeing (Hughes/McDonnell-Douglas) AH-64 Apache

Following experience gained in Vietnam it appeared that the US Army needed a dedicated anti-tank helicopter to replace the AH-1 Cobra, that was just an interim solution. The competition was won by the Hughes design, that was designated AH-64 Apache. Hughes model 77 has a slender fuselage, with a sort of cheeks along the lower sides of the fuselage, containing among others avionics. The crew sits under a two part, continuous canopy. The canopy opens at the sides; the top panels are fixed. The pilot in the back sits higher than the weapons operator in the front. Near the middle of the fuselage are two external nacelles with the turboshaft engines. They have a round plug in the intake. Just below are the short stub wings wing two weapon pylons on each. The Apache has a four blade main rotor and a four blade tail rotor as well. This tail rotor has a scissor shape, meaning that the angles between the blades is not equal. Except for the first prototype the tail rotor is placed high on the vertical fin, on the left side, but not at the very top. Below is an all movable horizontal stabiliser. Finally, the AH-64 has a fixed single wheel gear, with a rear braced main gear. The tail wheel it at the very end, below the stabilator.

Like many attack helicopters the rear seat is higher than the front seat, but on the AH-64 the crew sits under a single canopy with nearly flat panels. The side panels can be opened.

A typical feature of the Apache is the scissor type, four blade tail rotor: the angle between the blades is unequal. Also note the tail wheel at the very end of the tail boom.

Different versions

To distinguish the different versions of the AH-64 Apache you will have to look at

  • whether it has high or low mounted horizontal stabilisers
  • whether the main rotor blades can be folded or not
  • the presence of a dome on top of the rotor mast
  • the size of the sponsons or "cheeks" along the side of the fuselage
  • the shape of the main rotor tips


The YAH-64 was the helicopter that Hughes made for the tests against the Bell YAH-63. While many feature of the eventual AH-64A are already visible, the YAH-64 is still quite different. For a start, it has a T-tail and a tail rotor halfway the tall vertical fin. Furthermore, the canopy windows are different, as is the nose. Other differences are less obvious. On an updated version of the YAH-64 the horizontal stabilisers are located at the bottom of the tail boom.

The YAH-64 prototype already looks quite like the later AH-64A, but is still more different than the A model is from the D and E model. Especially note the T-tail. (photo: BG Charles E. Canedy, Deputy Director of Operations & Army Aviation Officer, Office of the Deputy Chief of Staff for Operations & Plans, Washington, DC/WikiMedia)

In a later version of the YAH-64 the horizontal stabilisers moved to the base of the vertical fin, that remain higher than on the production version though.

AH-64A Apache

The key feature of the original Apache, the AH-64A, are the size of the sonsons, or "cheeks" along the lower sides of the fuselage. They start near the front of the canopy , become higher and wider from there and end again below the stub wings. The main rotor tips are swept, but the chord remains the same as the main part of the rotor blade, i.e. both leading edge and trailing are swept with the same angle.

The AH-64A is especially recognised by the size of the sponsons along the lower sides of the fuselage, or "cheeks".

On this detail photo you can better see that the sponson runs from the front of the canopy to under the stub wings.

AH-64D Apache Longbow

On this upgraded Apache, the sponsons are much longer, starting at the sensors in the nose and continuing until after the stub wings. On the left side they are higher than on the right side. Moreover, The AH-64D can be equipped with the Longbow radar (hence the name), housed in a dome on top of the main rotor mast. Not all AH-64Ds are actually always fitted with this dome, so the size of the sponsons are the main recognition point, together with the main rotor tips. These are the same as on the AH-64A.

The UK version of the AH-64D was largely license-built by Westland, and called WAH-64 by them. In military service it became the Apache AH1 though. This version has different engines, but in externally the same nacelles. Additionally, it may have some different sensors, but as these have changed in the course of time (also on other AH-64Ds!), it is difficult to tell how you can use them to recognise an Apache AH1. Anyway, the British Apaches seem to always have the Longbow radar installed.

An Apache AH1 or the British Army Air Corps showing its Longbow radar dome and long sponsons.

This US Army AH-64D has engine exhausts pointing up, into the rotor wash. Also note the shape of the rotor tip.

The AH-64D has much longer sponsons, ending about halfway the nacelles. Also note the standard exhaust, straight aft.

AH-64E Apache Guardian

The third generation Apache is externally quite similar to the AH-64D, but has different main rotor blades. They are thicker and only the leading edges of the tips are swept, meaning that the tips taper. The UK equivalent of the AH-64E is the Apache AH2. So far, we still need to find out the external difference between the AH-64E and Apache AH2.

A full view of an Apache AH2, the British designation of the AH-64E.

Zooming in on the front you can slightly better see the tapered main rotor tips of the Apache Guardian.

Confusion possible with

Mil Mi-28


The Soviet counterpart of the Apache is the Mi-28 Havoc. Both helicopters are in many ways similar, except that the Mi-28 has a five blade main rotor, two separate canopies, a scissor type tail rotor on the right, a high mounted horizontal stabiliser on the left and higher placed stub wings. Other differences are smaller.



A lot is still unknown for this Chinese attack helicopter, but from the first photos that surfaced it appears to be similar in appearance to the Apache. The Z-21 has a five blade main rotor though, a regular four blade tail rotor on the right and likely more subtle differences. 

Harbin Z-19


The canopy and gear are a bit like on the AH-64, but for the rest the Z-19 is significantly different. The Z-19 has a fenestron and horizontal stabilisers with large endplates, which come from the Harbin Z-9. The same applies to the engines and (main) rotor system. (photo: Alert5/WikiMedia)

Changhe Z-10


The Changhe Z-10 has a fixed tail wheel landing gear and a scissor shaped four blade tail rotor like the Apache. The main rotor has five blades though and the canopies are separated. Moreover, the Z-10 has a distinctive body line along the fuselage and tail boom. (photo: 3GO*CHN-405/mjordan_6/WikiMedia)