Dave Eadsforth wrote:

In article , BUFDRVR
writes
Dave Eadsforth wrote:

However, how did the
formation attack compare with say a long string of B17s in trail, each
aiming individually?

In 1937, with career Army Air Corps crews, over Arizona with little wind it
worked great! In 1943 with crews that had been in service 18 months, over
Germany with flak and fighters...not so well.

The formation attack must be all or nothing,
whereas the trail attack must result in a number of well-aimed drops
amongst the average ones.

Except a two mile long train of B-17s looks like donuts rolling off the
production line to an Me-109 pilot.

Whoops - night time is not the best time for me to formulate a detailed
question!

I realise I said individual B17s (ouch!). What I meant to ask about was
a tactic I read about a while ago where Combat Wings would shake out
into individual Groups in trail at IP when a concentration of bombs was
required for a particular target. Are there any analyses of the
effectiveness of a succession of waves of Combat Wings over the target
versus a succession of formations of bombers broken down into individual
Groups?

If someone could give me a thumbnail sketch of how a series of B17
Combat Wings usually approached a target, and what specific options for
attack were possible between the IP and the RP I would be very grateful.

Depends on the period, but typically the wings would be 2-5miles in trail of each
other. At the IP, each wing would try and get the groups in trail, by the lead
group making a regular turn and the flanking (high and low ) groups turning early
or late. However, groups would stay at their same heights for bombing, which made
reassembly into the wing formation after exiting the target easier.

In practice, it often was difficult or impossible for the groups to get into trail,
so you might have the groups actually approaching the target on convergent courses,
sometimes simultaneously. This could cause problems if one group flew under
another at bombs away - see the fairly numerous photos of B-17s or B-24s destroyed
or damaged by being bombed by a/c of a higher group. For example, there's a widely
published sequence showing a B-17 under another which releases its bombs, one of
which removes the left horizontal stabilizer and elevator of the lower a/c, which
then gradually departs controlled flight and is lost. It could get even worse,
when one or more _wings_ approached the target at the same time, usually because
someone had missed turning at the proper IP, or else one of the formations had gone
around again because they hadn't bombed the first time (which made the lead
bombardier and the mission commander very unpopular with the other crews).

Depending on the size of the target and the number of wings, following wings might
have the same or a different aimpoint. Later in the war with more wings, the
latter practice was more common, as it was found that smoke and fires from the
earlier groups bombs often made it impossible for the later groups' bombardiers to
spot the original aimpoint. Indeed, the 8th Operational Research section did a
study which showed that group bombing accuracy directly correlated with where the
group was in the sequence; the earlier a group bombed the target, the more
accurately it bombed. See Stephen L. McFarland's book "America's Pursuit of
Precision Bombing, 1910-1945," for everything you're ever likely to have wanted to
know (and a lot more) about U.S. and other countries bombsight development and use,
as well as accuracies achievable, production issues, factors such as the above
which caused bombing errors, etc.

In 1944 and especially in 1945 when attacking smaller, less well-defended targets
with smaller formations, it became common to once again bomb by squadrons instead
of groups, precisely to avoid the sort of spillover wastage that larger bombing
formations caused.

As to the technique of individual bombers aiming and bombing a target in a stream,
AFAIK that was only practised by the RAF at night, from 1944 or so on (for
precision attacks, that is). This appears to have been adopted because Churchill
was worried about French civilian casualties from collateral damage if the
transportation plan was adopted. However, it was found that Bomber Command (well,
5 Group anyway, usually led by 617 as target markers), was able to bomb marshalling
yards accurately and keep the collateral damage down, by bombing individually
instead of in formation. Using large formations would have caused too much
spillover damage -- even with a 100% accurate MPI, the bomb coverage area of a big
formation was so large that numerous bombs were bound to hit outside the target
area. With individual bombers, even the occasional gross aiming error resulted in
fewer bombs hitting civilian areas. Note that this technique was only considered
possible in areas where the defenses were rather light, i.e. over France at night,
because the bombers lacked mutual support for defense. It's also true that such a
risk was considered politically necessary to avoid allied civilian causualties,
whereas by 1944 (at least), none of the allied commanders cared all that much if
collateral damage from spillover due to bombing in formation killed large numbers
of German civilians.

Guy