In article , DeepSea
wrote:

Not much mention of Dive Bombers there! The Luftwaffe _did_ have
Dive-Bombers, these were aircraft specifically designed for
Close-Air-Support of advancing troops and AIUI such aircraft were
directed by their pilots along a line-of-sight towards their target;
the aircraft's systems automagically performed a J-curve manoeuvre
which had the effect of taking the aircraft away and above the target
while the ordnance continued along the line-of-sight to impact. Such
aircraft were tasked against known targets, predominantly the Chain
Home stations and airfields. AIUI, the aircraft-weapon systems was a
success but not many Teutonic aircrew made a second sortie.


That would explain the British complaint with the early P-51's lack of
high altitude performance. Based on the information I had, I (apparently
incorrectly) assumed that there was no need for a fighter with good high
altitude performance - I thought that most of the action during the BoB
was down low where the early P-51 was actually pretty capable.

The RAF were understandably further ahead of the power curve than USAAC
with regards to what equipment was needed for the air battle.
They had the recent experience of BoB and previously BoF.

The German bombers came over in the mid-teens (probably due to oxygen
issues) with fighter cover that started out in the high teens, but as the
battles
progressed and each side sought the advantage, the fighter cover started
coming over in the low to mid-twenties.

Thus the race for better performing fighters at "high" altitude.

The USAAC was still stuck in the opinion that fighter battles would take place
in the mid-teens. This didn't change until the US entered the war.
That's why NAA had shown the Mustang I to the AAC with the Allison engine.
It performed well at the mid-teens. It's what the AAC asked for, and you
have to offer the customer what he wants.
The British took them that way out of necessity, with their eyes open, and
assigned them to roles that didn't require high altitude, until a fix
could be found.

The USAAC wan't that interested in the Mustang at first because they already
had several figher projects well underway (P-38, P-47).

WRT German dive bombing: the type most used for that was the JU-87 Stuka
and they were such dead meat for the RAF that the Luftwaffe stopped sending
them over early on in BoB.

cheers

--
Harry Andreas
Engineering raconteur