Number of airworthy US airplanes

[rammjaeger]

I was just cleaning up a bit and re-discovered Leonard Ayres „The War with Germany, A Statistical Summary“ together with notes about the strength of US-frontline aviation units from another source.

One thing makes me wonder. In 1920 Ayres states about the Meuse-Argonne engagement the following:
“During the six weeks' struggle, the losses were heavy, but replacements were brought forward so rapidly that at the last stage of the action the available American strength was greater than at the start.”

The other notes – original source is unknown to me – claim another thing. It is stated the Americans had 646 airworthy airplanes on the front before the offensive, but only 579 airworthy machines were left on 15. October and only 457 airworthy airplanes left EOW.

What is going on here?
Which source is correct?
Or is the difference result of a different meaning of “available” and “airworthy” aircraft?
(An airplane could be available but not airworthy because of the need for repairs after battle damage or a crash.)

Who can enlighten me here?
Is there any statistic counting the frontline strength per month in available and airworthy airplanes?

VBR
Rammjaeger

[Epee]

Perhaps Ayres is speaking only of aircraft assigned to the M-A action and not the total frontline strength.

[TomVrille]

The following item may be of some help. It is a quote from Gen. Billy Mitchell in Leaves from My War Diary.

"My reports on the morning of November 11 showed that I had present on the front in the hands of American units 740 airplanes. Of these, 528 were of French manufacture, 16 were of British manufacture, and 196 were of American manufacture."

The condition of these aircraft is not stated, so it is unclear how many could be considered airworthy.

[Dan_San_Abbott]

Rammjaeger:
I am reading this as total aircraft on hand in France (740)and aircraft at the front with the First and Second Armies:
1. Before the offensive (25 September 1918?) 646
2. On 15 October 1918................................579
wastage 67=10.3%.
3. On 11 November 1918.............................457
Total losses from 25 September 1918, 189 in 47 days = 4.02 /day=.6%aircraft /day. That is a sustainable percentage. For comparision, the 8th Air Force in WW2 1943 was 10%+ /day. That was not sustainable. They had predicated the 25 mission crew rotation on less the 4% loss rate.
Hannes, The Pursuit Squadrons equipped with the SPAD XIII had a terrible serviceability rate of less than 50%, Hissos crapping out, oil leaks, the propeller shaft gears going south, leaky radiators and that is reflected in the low airworthy numbers. I don't think the D.H.4s, Breguets, Salmsons had those kind of problems. Their problems were the Jagdstaffeln in the German
3., 5., C., 19., A., B. Armeen. They had them for breakfast!.
Blue skies,
Dan-San

[rammjaeger]

Thanks for the helpful answers.

I would risk this interpetation of the presented numbers:
Gen. Mitchell reports 740 airplanes for the front on EOW.
Serviceable were only 457 (= 61,8 %).

That seems to be low but if the SPAD units had only ca 50% serviceability rate (means 150 serviceable of ca 300 SPAD) then we come up with a serviceablity rate close to 70 % for the non-SPAD types (307 serviceable non-SPAD from a total of 440 non-SPAD). That sounds reasonable to me.

Dan-San, I agree that the US-airplane losses of WWI did not meet the losses in some "heavy" periods of WWII but the wastage between 26.9. and 11.11. was surely higher than 189 - because there must have been delieveries of airplanes to the frontline units in this time! (Ayres words indicate that too.)

Therefore the formula for wastage (between 26.9. and 11.11.) should be:
wastage = 189 + number of airplanes delivered to frontline units between 26.9. and 11.11.1918.

That means the higher the (unknown number of) deliveries the higher the wastage in this time.

Despite of additional deliveries the number of serviceable airplanes at the front shrinked. I assume the causes were many-sided: Technical problems, combat losses, non-combat losses and maybe some knots in the logistical pipelines.

VBR
Hannes

[Dan_San_Abbott]

RammJaeger:
The U.S.Army had 740 aircraft "at the front" on 11/11/18. At the depots in boxes, assembled, test flown, problems, test flown accepted awaiting delivery plus machnes in the repair depots and all the machines assigned to 45front squadrons. There were 45 U.S. Army squadrons assigned to the First and Second Armies. With a nominal strength of 18 aircraft= 810 aircraft. Which means there are a lot of squadrons under strength.
I don't know how the U.S.Air Service counted damaged and reparable aircraft that managed to land. I am going pursue this further and see what I can find.
I'll get back to you.
Blue skies,
Dan-San

[rammjaeger]

Thank you and thanks in advance for your efforts, Dan-San!