USAAC ground-attack/dive bomber (North American A-36 Apache)

[gjs238]

The A-36 was relatively short lived.
Perhaps the P-51 wasn't the ideal platform for this role, but perhaps the concept could have/should have been executed in another platform???

The USAAC tried some naval designs like the A-24 Banshee and A-25 Shrike, with what seems to be limited success.

Perhaps a fighter based platform would have been better?

Or was the concept of a ground-attack/dive bomber flawed?

 

[bobbysocks]

I would have to dig it up but the guys that flew them loved the A-36. They claimed it could dive straight down and give them a positive target aquisition....however the down side was they guners on the ground had a stationary target to shoot at. i will see if i can dig up the site or the stories for you.

 

[Siegfried]

One would think that with a stunning airframe
as the P-51A one would not convert production
to the A-36 dive bomber variant but use the P-40
as a dive bomber instead thus leaving the
P-51 as a fighter.

There may have been technical reasons such as
the thicker wings of the P-51A allowing easier
mechanical integration of the split dive brakes or
placement of P-40 undercarriage. It may also
have been a way North American could
wangle a sale to the USAAF or North American
simply had the idea and Curtiss didn't.

Dive bombing seems to have been a US Navy speciality
and used by the Royal Navy on the Skua.

What is fascinating about the A-36 is its ability to
be both a full screaming dive bomber as well as
a very fast fighter aircraft. I don't think many
other aircraft were able to match this.

It's somewhat puzzling as to why the Luftwaffe didn't
copy this dive brake arrangement for its single seaters
or for the matter anyone else; though these type of
brakes were used on the Me 410 for instance.

By 1942 two new bomb sights were in service with the Luftwaffe.

1 The Lotfe 7C, this was a gyrostablised bombsight that had variable
speed drives that could be trimed in speed to track a target on the ground
to theraby establish true ground speed and therefore wind drift and
automatically calculate an offset.

More or less similar to the Norden.

2 The Stuvi 5B was a continuous computing shallow dive bombing sight.
It put a continuous impact point on to the target so that for instance
a Ju 88 without dive brakes and in a 20 degree dive could bomb accurately
in a shallow dive from say 8000ft to 5000ft.

The this bomb-sight was also used by Ju 87 Stuka; it was not suitable
for aircraft that didn't have good downward vision or alternatively
those that could go in a steep dive.

The British Mk XIV bomb-sight could also slide bomb.


s it seems dive bombing was no longer so important, except at sea, where the
small target the aircraft made reduced chance of a hit.


The allied moved to rockets. The Germans started to develop a computing
bombsight suitable for fighters that worked through the gunsight called
the TSA-2D. They also started to introduce rockets in the final months of
the war.

I'm curious to know if the US had or used any shallow dive or slide bombing sights.

It seems the doctrine was just to use a formation of Medium bombers such as
B-26 or B-25 to do a drop from medium altitude: say 8000-12000ft

 

[norab]

The Vultee A-31 used essentially the same dive brakes and was capable of a vertical dive

 

[davebender]

I believe lack of armor protection was the A-36 achilles heel. The U.S. Army Air Corps could have added armor but I get the impression they didn't really believe in light bombers anyway. Otherwise they would have made greater use of the A-20.

 

[drgondog]

Hap Arnold didn't have procurement money left for fighters but wanted to keep the NAA building the P-51 but he did have funding left for dive bombers - Voila, the A-36 was born.

 

[model299]

It was my impression from books and magazines I've read that the A-36 program was designed to keep the North American project alive, as the "powers that be" were supposedly telling the AAC that "You've already got the P-40, what do you need THIS aircraft for."

I've also read that, with age, the reliability of these airbrakes proved problematic, and that on examples still in the field, they were simply wired shut.

Edit: Eh, spanked by drgondog!

 

[davebender]

Then why not add armor protection for the pilot, cooling system etc. to make the aircraft successful in the CAS role? Otherwise you are just throwing an aircraft and pilot away.

 

[model299]

Then why not add armor protection for the pilot, cooling system etc. to make the aircraft successful in the CAS role? Otherwise you are just throwing an aircraft and pilot away.

One word. Weight.

 

[davebender]

Ju-87Ds, Il-2s, Me-410s and Hs-129s all managed to fly despite having significant armor protection. I think the A-36 will still fly also after adding 500 lbs of armor. Flying a CAS aircraft without protective armor is little more then a suicide mission.

 

[vanir]

The US Navy, FFAF and RAAF were about the only people in the world who wanted dive bombers after 1942. Can't remember where the British unloaded their Skuas but it was like they wanted to forget they existed, even our Vultees wound up in our hands because nobody else wanted them. We used them as level bombers and fighter-bombers mostly, even as heavy recon-fighters, not as traditional dive bombers often.

 

[tomo pauk]

VVS also wanted dive bombers, the Pe-2s were their birds.

 

[davebender]

German Me-210C / Me-410A was a dive bomber.

The RN determined that the American made F4U fighter also made a decent light bomber. I think that's why the RN gave up on purpose built dive bombers such as the Skua, SBD and SB2C.

 

[gjs238]

All this being said, I wonder what kind of results the A-36 achieved.
If favorable, why was the type not continued - or the concept continued in another platform (such as with a radial engine?)
If unfavorable, why? Poor platform, poor armor protection, etc.?

I'm sensing an overall distake for dive bombing by the USAAC.
It seems they tried the concept with several platforms.

 

[Shortround6]

Dive bombing works really great if your opponent has
A. Few, if any fighters to attack the dive bombers.
B. Few, if any anti-aircraft guns to shoot at the dive bombers.

While an A-36 could do a much better job of defending itself than an A-24 (Dauntless) or A-25 (Helldiver) that is AFTER the bombs are dropped. If attacked before the bombing run and the bombs are dropped it is a "mission kill" for the defender even if they don't shoot down a single plane. A dive bomb run sets up the dive bomber in a relatively straight, predictable flight path that is a blessing to a light anti-aircraft battery or even AA machine guns regardless of the type of engine.

 

[davebender]

You've got no other choice if you want to hit the target with unguided munitions. That's why the Me-210 / Me-410 had 900 lbs of armor to protect the aircrew and critical engine components. It also had some of the best protected fuel tanks on any WWII aircraft.

If the USAAC want the A-36 dive bomber to succeed then it needs serious armor protection also. You cannot protect an aircraft against 20mm fire but a dive bomber should be capable of surviving a considerable amount of machinegun fire.

 

[Milosh]

The A-36 flew 23,373 missions and lost 177 a/c (enemy air and ground actions). They claimed 84 e/a and 17 on the ground.

23,373/177 = 697 missions per loss

 

[davebender]

The Plane That Saved The Mustang: The North American A-36 Apache

Only five hundred A-36's were built. The results of flight tests conducted at Florida's Eglin Army Air Field seemed to reinforce the Army's doubts about dive-bombing, and the A-36.

The A-36 dove at speeds approaching 500 mph; the brakes only reduced the speed to about 350mph. Unfortunately, one of the test airplanes crashed because it lost its wings during a vertical dive. Not surprisingly, Army officials decided that the airplane had great diving capabilities for a fighter, but dove too fast for a dive – bomber. As a result of all this, the Army restricted the plane's dive-angles to 70 degrees. In addition, the evaluators at Eglin recommended that the A-36 be used mainly as a low-altitude attack airplane, and that the dive brakes be eliminated.

One of the challenges faced by A-36 pilots was a lack of specialized training in dive-bombing techniques. A few Navy and Marine instructors were "loaned" to the Army, but most Army aviators learned their trade through improvisation. Dills recalls:

"We had no dive-bombing training in flying school, but when I got to my RTU (Replacement Training Unit) in Sarasota, Florida, they had P-40's. We had little twenty five or fifty pound things with little explosive charges, and we'd drop them on the bombing range. We glide bombed at a sixty degree angle, but we didn't go vertical. People just didn't do that – in any airplane. It would have scared the hell out of them, I guess. But once we got over "there", people starting shooting at you and you did things that you never would've thought of before. Vertical dives worked so well in the A-36, that we didn't think twice about doing it in P-40's (later on) – with NO dive brakes!

Reading this article I get the impression A-36 dive brakes were inadequate to slow the aircraft for accurate bombing. Inadequate bomber training was the final nail in the A-36 dive bomber coffin. These problems may have been fixable but the USAAC made no serious effort in that direction. Instead the A-36 ended up being used as a low altitude fighter in a manner similiar to P-40s and P-47s assigned to the Mediterranean theater.

 

[Milosh]

Gee Dave, the Stuka dived at a 60-90° angle, holding a constant speed of 350-370 mph. The Ju87 must therefore have been inadequate.

 

[davebender]

Perhaps the A-36 bomb site wasn't as good as the Ju-87 bomb sight. Otherwise it's difficult to understand why it couldn't bomb accurately at similiar dive speeds.