Dive bombing discussion

[grizz441]

(Image removed from quote.)

Looks dangerous alright.   

That's your mustang right?

[Chalenge]

     Apparently a very popular urban legend, Challenge should know better 

Go look at an A36 sometime and you will see that there is nothing to wire the dive brake to except the other dive brake and since they move in unison there would be no reason to add wire. Not only is this urban legend its ignorant.

[Chalenge]

Dan, the dive brake were to be extended before the dive began. If they were extend once the dive had begun then there was the possibility of them not extended equally.

I dont think thats right either. Airflow alone isnt going to stop these dive brakes from extending. The problem is that the procedure needed to be followed properly or too much speed would build up making it a problem to pull out of the dive at all. In the same book 'Dan' is trying to quote (and its not in there) he describes the affect the first military pilots had during gun trials of the Mustang. Diving the plane from 12k took the airplane to speeds they had never flown before (this was the "hey we need this plane in the war" moment). If you follow procedures you dont crash its that simple.

[MiloMorai]

I dont think thats right either. Airflow alone isnt going to stop these dive brakes from extending. The problem is that the procedure needed to be followed properly or too much speed would build up making it a problem to pull out of the dive at all. In the same book 'Dan' is trying to quote (and its not in there) he describes the affect the first military pilots had during gun trials of the Mustang. Diving the plane from 12k took the airplane to speeds they had never flown before (this was the "hey we need this plane in the war" moment). If you follow procedures you dont crash its that simple.

See the bottom of pg 61 of the Gruenhagen book.

[Ack-Ack]

Daughter getting married today. 

Congratulations Dan!


ack-ack

[Ack-Ack]

Go look at an A36 sometime and you will see that there is nothing to wire the dive brake to except the other dive brake and since they move in unison there would be no reason to add wire. Not only is this urban legend its ignorant.

The problem with the dive brakes is that due to the hydraulics they would sometimes not deploy in unision, which as Dan explained, led to some units to wire them shut and not use them.  Other units continued to use them and the problem was eventually found to be caused mostly when the dive brakes were deployed "after peel off".

ack-ack

[Chalenge]

The problem with the dive brakes is that due to the hydraulics they would sometimes not deploy in unision, which as Dan explained, led to some units to wire them shut and not use them.  Other units continued to use them and the problem was eventually found to be caused mostly when the dive brakes were deployed "after peel off".

ack-ack

Incorrect. The problem was that after high speed was developed and they were deployed they would not always extend in unison (necessarily) which is true enough but the rolling motion would throw off accuracy (which is what Gruenhagen says). At high speed the dive brakes do nothing to slow the airplane down but they do prevent further speed to build. The problem occurs only if you are already too fast. Gruenhagen also correctly states that the proper procedure is to climb to 12-15k deploy the brakes and then initiate the dive. Throwing off accuracy is not going to panic pilots into asking for the brakes to be wired shut. However... the Mustang at this point in the war did have the highest accident rate in the war. The reason was that pilots were shedding wings from excessive speed buildup (450 mph**)... the A-36 units were ordered not to exceed 70 degrees*** in a dive for that reason.
 
Capt. Charles E. Dills, 27th Fighter-Bomber Group, 522d Fighter Squadron, XIIth Air Force emphatically stated in a postwar interview:

"I flew the A-36 for 39 of my 94 missions, from 11/43 to 3/44. They were never wired shut in Italy in combat. This 'wired shut' story apparently came from the training group at Harding Field, Baton Rouge, LA."

*

At Harding Field the P-51s and A-36 aircraft were repaired and maintained (Hardings purpose in WWII). Harding Field was not a training facility for the Mustang types.

The first thing you will ever learn about the legend of the Mustang is the two mistruths. One is the dive brakes of the A-36 and the other is that the A-36 was named the Invader which was never accepted officially. Just because a few men in the field named it that doesnt make it official.

Just because one mechanic says "they should wire those things shut" doesnt mean there was a terrible problem with them.

Myth and urban legend busted.

* Hess, William N. Fighting Mustang: The Chronicle of the P-51. New York: Doubleday and Company, 1970. ISBN 0-912173-04-1 p. 13
** Freeman, Roger A. Mustang at War. New York: Doubleday and Company, Inc., 1974. ISBN 0-385-06644-9 p. 45
*** Grinsell, Robert. "P-51 Mustang". Great Book of World War II Airplanes. New York: Wing & Anchor Press, 1984. ISBN 0-517-45993-0 p. 69

[Masherbrum]

Incorrect. The problem was that after high speed was developed and they were deployed they would not always extend in unison (necessarily) which is true enough but the rolling motion would throw off accuracy (which is what Gruenhagen says). At high speed the dive brakes do nothing to slow the airplane down but they do prevent further speed to build. The problem occurs only if you are already too fast. Gruenhagen also correctly states that the proper procedure is to climb to 12-15k deploy the brakes and then initiate the dive. Throwing off accuracy is not going to panic pilots into asking for the brakes to be wired shut. However... the Mustang at this point in the war did have the highest accident rate in the war. The reason was that pilots were shedding wings from excessive speed buildup (450 mph**)... the A-36 units were ordered not to exceed 70 degrees*** in a dive for that reason.
 
Capt. Charles E. Dills, 27th Fighter-Bomber Group, 522d Fighter Squadron, XIIth Air Force emphatically stated in a postwar interview: *

At Harding Field the P-51s and A-36 aircraft were repaired and maintained (Hardings purpose in WWII). Harding Field was not a training facility for the Mustang types.

The first thing you will ever learn about the legend of the Mustang is the two mistruths. One is the dive brakes of the A-36 and the other is that the A-36 was named the Invader which was never accepted officially. Just because a few men in the field named it that doesnt make it official.

Just because one mechanic says "they should wire those things shut" doesnt mean there was a terrible problem with them.

Myth and urban legend busted.

* Hess, William N. Fighting Mustang: The Chronicle of the P-51. New York: Doubleday and Company, 1970. ISBN 0-912173-04-1 p. 13
** Freeman, Roger A. Mustang at War. New York: Doubleday and Company, Inc., 1974. ISBN 0-385-06644-9 p. 45
*** Grinsell, Robert. "P-51 Mustang". Great Book of World War II Airplanes. New York: Wing & Anchor Press, 1984. ISBN 0-517-45993-0 p. 69

Hey know it all, Milo beat me to it...

See the bottom of pg 61 of the Gruenhagen book.

[Chalenge]

Hey know it all, Milo beat me to it...

Yo! Read what I just posted.

Obviously what happened was the pilots were reporting to maintenance: "the hydraulics are dropping power and throwing off my aim" to which the mechaincs (after many such complaints) replied: "The stupid things should be wired shut."

The brakes were never wired shut bloviator.

By the way... most of the experienced pilots ignored the order to limit their dive angles.

[Baumer]

Chalenge, I was going to point out how 1 pilot agreed with you (Charles Dills) and that it wasn't common for them to be wired shut.

HOWEVER

You have once again shown the AMAZING ability to twist a few statements around and draw ridiculous conclusions. It's astounding what you think is obvious from your imagined pilot to mechanic discussion.

And if, as us say, the experienced pilots ignored the limits they OBVIOUSLY didn't do it for long, given how many shed parts and crashed. There's a reason the old saying goes, "There are old pilots and there are bold pilots but there aren't many old bold pilots." If you read anything from Mr. Dills website you'd pickup on the fact that the A-36 was tricky to handle in a bomb run. Speed would build up faster than you'd anticipate making the pull out very challenging.

Here's Mr. Dills website for anyone that cares to read it, some pretty interesting stuff. http://www.charlies-web.com/WWII_med/index.html

[MiloMorai]

Incorrect. The problem was that after high speed was developed and they were deployed they would not always extend in unison (necessarily) which is true enough but the rolling motion would throw off accuracy (which is what Gruenhagen says). At high speed the dive brakes do nothing to slow the airplane down but they do prevent further speed to build. The problem occurs only if you are already too fast. Gruenhagen also correctly states that the proper procedure is to climb to 12-15k deploy the brakes and then initiate the dive. Throwing off accuracy is not going to panic pilots into asking for the brakes to be wired shut. However... the Mustang at this point in the war did have the highest accident rate in the war. The reason was that pilots were shedding wings from excessive speed buildup (450 mph**)... the A-36 units were ordered not to exceed 70 degrees*** in a dive for that reason.
 

Dah. Isn't that what I said?

the dive brake were to be extended before the dive began. If they were extend once the dive had begun then there was the possibility of them not extended equally.

Now lets look at what Ack-Ack said:

they would sometimes not deploy in unison

And now what you said:

Incorrect. The problem was that after high speed was developed and they were deployed they would not always extend in unison

 

[Chalenge]

Baumer: No... the experienced pilots ignored the orders because they were doing things the right way. If you deploy the dive brakes before you initiate the dive there is not a problem with assymetric deployment. AGAIN: assymetric deployment does not cause a problem in itself. It does cause inaccuracies in bombing ONLY.

Milo: Im sorry if you were in agreement with me all along. It seemed (seems) to me that you are implying there was a problem with the dive brakes and that THEY were the cause of broken/crashing A36s and WERE wired shut.

Again: All I am saying in all of this is the the dive brakes WERE NEVER wired shut. Problems with the Mustang did occur. Wired dive brakes was never a solution.

Tricky does not make an airplane (or its dive brakes) fatal.

[MiloMorai]

I can not find you mentioning anything about the the deployment procedure of the dive brakes before I did. But, I can see how you arrived at that conclusion. (see below)

I dont think thats right either. Airflow alone isnt going to stop these dive brakes from extending.

This totally opposite to what Greunhagen said on pg 61 of his book.

"Hydraulic control systems had not been developed sufficiently to allow extension of the brakes after high speed had been attained. In this configuration it was possible to achieve unequal extension of the brakes........"

[Chalenge]

What he is saying is the dive brakes do not extend simultaneously if excessive speed has already been met. This causes a rolling motion that can be countermanded by the joystick but that will still throw off the bomb aim point. If the brakes are extended by procedure (before the dive) there is no problem. The hydraulics of the system was not quite up to pushing both out once speed had built up but that didnt stop them from coming out all the way (or at all). Once one was fully extended the other would extend also.

You see the pilots would be in training on the A36 and be required to complete a certain level of competency in their dive bombing before they could move forward to deployment. If they could not make the grade they would be dropped or reassigned. The dive brakes gave them a target of their anxieties and so they complained to maintenance about the hydraulics. The fact remains that proper procedure led to zero problems.

If you ever make a trip to Chino and meet Steve Hinton ask him what he has experienced in the A36A and he will confirm this (and tell you that modern hydraulics cured the problem).

[grizz441]

I'm just going to assume Chalenge is wrong because he is Voss.