Thursday, July 23, 2015

Douglas AD (A-1) Skyraider Pylons

The configuration and orientation of Skyraider weapons pylons comes up from time to time. They are usually not depicted correctly in model kits. This is a work in progress.

The pylon on the inboard wing was perpendicular, i.e. hanging straight down (except on the unique pylon for the big podded radar: see The pylons on the outboard wing panel were perpendicular to the wing instead; they were also not evenly spaced.
The view from the side.

The outboard wing pylons were also not "swept" at the same angle as the leading edge, i.e. the most outboard one was closer to the wing leading edge than the most inboard.

The center-line pylon on the later ADs:

Note the interface with the oil cooler outlet: the forward end of the pylon is much deeper because it sweeps up into the duct (don't be mislead by the shadow).
 I'm told that the Trumpeter 1/32 center pylon does not angle upward from front to rear as it should.

Early ADs had much smaller and less capable AERO pylons on the outboard wing panel. See

AD-1s through -4s had a smaller inboard wing pylon than the 5/6/7. The later, longer pylon introduced on the -5 was reportedly necessary to move certain stores farther forward for ground clearance. It also added provisions for the 30-inch lug spacing required for some stores. In addition, it may have been desirable to move the loaded center of gravity forward, particularly on the -5.
Thanks to Ed Barthelmes for a pretty good drawing of the early pylon. However, it has been hard to pin down the exact location of the early pylon on the wing from available drawings. The above drawing is my best guess at the moment.

Here is a direct comparison of the World War II era 1,000 and 2,000 lb bombs on the earlier pylon.
Early ADs did not have an external center pylon so that a torpedo could be carried. The shackle was mounted within the fuselage along with provisions for an explosive cartridge that propelled a bomb downward away from the airplane when dive bombing so that it would not hit the propeller.
Illustration from Ed Barthelmes

As a result, the bomb or torpedo was snugged up directly beneath the fuselage.
U.S. Navy via Steve Ginter


  1. Hi, I'm currently making a model of an AD-3 Korean War era. I've seen some photos that show the centre-line pylon absent and instead the bomb attached straight on to the fuselage. Can you confirm if this is true, thanks in advance.

  2. Oops - missed that difference. On the early ADs, the center shackle was mounted in the fuselage so the bomb was snugged up against the belly. See the added detail provided in the post.

    1. Thanks for that, much appreciated.

  3. From David Collier, with respect to what I call the centerline rack: "We called them, ejector rack or Douglas bomb ejector, never centerline rack. Our AD-4s had the rack as shown in the pictures which could only carry bombs with 14” space between lugs. Our AD-5Ns (Which were brand new when we received them in 1955) had the ejector rack modified to have suspension hooks spaced at 14” and 30”. The larger spacing was used for nuclear stores and the large streamlined tanks. The AD-4Bs that we had had the same bomb ejector as the AD-5N but without the streamlined fairing.

    Our AD’s never carried any nuclear shapes. We never loaded a 2000 pound bomb or low drag fuel tank on the center rack, only on the Mk-51 wing racks. We never fired a bomb ejector cartridge because the ejector had to dissembled and cleaned if a cartridge was fired. All tanks and bombs carried on the centerline rack could only be released by using the manually operated emergency rack release."