WalterM140 wrote:

Once air superiority was available the RAF flew their
daylight missions in loose gaggles of 2-4 aircraft staggered
in height to minimise flak damage.



That might have been influenced by the fact that no other aircraft type could
fly in the tight formations used by the B-17.

That's a question of stability and control forces. The B-17 was easier to fly in
formation than the B-24, but I have no idea how the British heavies stacked up.

I've heard that B-26s could also fly in very tight formations, but I shouldn't
think as at high an altitude as the B-17.

Not even close, owing to the engine supercharging.

B-17's could maintain formation at heights almost twice as high as the altitude
at which Bomber Command usually operated, either by day or by night.

Again, due to the superchargers. Both US mediums and the British heavies used
single-stage two-speed superchargers while the B-17 and B-24 used turbochargers
(feeding superchargers). That generally gave them max. power and top speeds ain
the range of 13,500 - 15,000 feet. A couple of years ago a few of us decided to
find out what it would take to boost RAF heavies to B-17 or B-24 formation cruise
heights. Given the available British engines, they could only have used two-stage
two-speed Merlins, 60, 70 or 80 series. Those were all being used by Spit 8/9/16s,
late model Mossie bomber/recon a/c, and of course Merlin P-51s. Major changes in
production lines (and the a/c) would have been required to provide enough for the
heavies as well.

Our conclusion was that the simplest and quickest method for the Brits to go over
to US style daylight bombing against well-defended targets in the fall of 1943 was
to use B-24s diverted from US groups in training (the 8th preferred the B-17), at
least until they could produce a high altitude bomber engine (preferably a Bristol
Hercules air-cooled radial, either turbocharged or with a two-speed supercharger)
in adequate numbers. By night most of them were able to cruise individually in
the 19 - 23,000 foot range, but formation flying limits the performance to the
worst a/c, and also requires some power in hand for throttle jockeying and
formation turns. So we figured they were likely restricted to tight formation
flying at altitudes of around 18,000 or at most 20,000 feet for Lancs or Halifax
IIIs, although we knew we'd have to lighten the bombloads to get them that high
(owing to the need to increase the defensive armament, armor, crew, and fuel
loads).

Guy