#1 Jet of World War II

The Revolution Will Not Be Televised wrote:

On Fri, 18 Jul 2003 01:04:53 -0400, (Peter
Stickney) wrote:

snip much

[Lanc altitude on ops]

While it doesn't get talked about much, the Lancaster was a fairly
height-limited machine. The usual heights on a raid into Germany were
between 15,000, and 20,000', depending on the amount of fuel burned,
and the particuar airplane.

By the winter of 1943-44, planned height bands for Lanc squadrons in 5
Group (which I have researched) were often 20-22,000 feet. The actual
bombing height was rarely much over 20,000 feet, and often a lot
lower, depending on weather and individual aircraft characteristics.
On operational conditions, with a full load, and winter weather to
deal with, they really did have difficulty getting over 20,000 feet.
The most common bombing heights (excluding exceptions like the
Peenemunde raid) seem to have been around 18,000 feet.

Odd that you should mention that, as Middlebrook ("The Nuremberg Raid") says
that a/c of all the Groups on the mission (with the exception of No. 1 GP;
see below), whether Lanc or Halifax, were evenly assigned to one of four
cruise heights -- 20, 21, 22, or 23 thousand feet. Naturally, some a/c were
unable to get that high or anywhere close to it. One crew flying a very sick
or tired Lanc couldn't struggle above 12,000 ft. but pressed on regardless;
as it turned out it probably saved them on that mission because the fighters
were up in the stream several thousand feet higher. A few a/c proved capable
of much better when the Jagdwaffe got into the stream and the experienced
crews decided that rigid adherence to assigned altitudes was stupid under the
circumstances, and decided to get the hell out of it by climbing (and more
than a few got rid of some bombs to lighten the a/c). One crew in a
brand-new Halifax (like all Halifaxes by that time, carrying an
all-incendiary and thus lighter load than the Lancs, to improve their
altitude performance) was delighted to discover that they were able to get up
to 26,000, and cruised happily along over the carnage a few thousand feet
below. The exception was 1 Group, whose philosophy was to carry max. bomb
loads on every mission, and who asked if they could fly at 13-16,000 feet to
take advantage of some predicted cloud at that level. They were granted
permission to do so until IIRR they reached the Rhine, at which point they
were supposed to climb to the same heights that everyone else was (supposed)
to be at. Unfortunately for them, the predicted cloud didn't show up.

After shedding the 5-7 tons that it was
delivering over the target, it would certainly have been able to
return at a much higher altitude than it went in.

Hence early jettisoning of bombs to reach bombing height, or climbing
after bombing. This is the sort of real context that tends to get
ignored in the interminable and ahistoric B-17 vs Lancaster
nationalist posturing. One of the trade-offs for the Lanc's higher
bombload was lower operating altitude [although this was also down to
the different engine outputs at different hieghts].

In addition to the engine differences, there's the considerable difference in
fixed weights (carried both to and from the target) due to extra crew, armor,
guns, turrets etc., and the extra fuel required for formation assembly (an
extra 1/2 to 2 hours before setting out), climb to higher cruise altitude and
flying in formation (throttle jockeying). When Pete and I went through the
exercise of turning the RAF heavies into day bombers a few years back, it was
apparent that using Lancs in formation by day against the same targets that
U.S. heavies were attacking, and with the same equipment, procedures and
tactics, would require a decrease in bombload of between 2,000-5,000 lb. to
reflect this, even assuming we refit them with two-stage Merlins to give them
sufficient power at altitude (and those engines each weigh ca. 200 lb. more
than the single stage jobs, which decreases the useful load for the same
MTOW, or requires an increase in MTOW and thus a decrease in climb
performance, higher accident rates, etc.). In short, design and equip them
to do the same job and they'll do it with payloads within a couple of hundred
pounds (either way) of each other. The whole Lanc vs. B-17 argument is just
ludicrous.

Guy

Subject: #1 Jet of World War II
From: Guy Alcala
Date: 7/23/03 4:40 AM Pacific Daylight Time
Message-id:

Hence early jettisoning of bombs to reach bombing height, or climbing
after bombing. This is the sort o


You mean they had to dump their bombs to get to bombing altitude?? Once they
had no bombs what is the point of getting to bombing altitude???

After shedding the 5-7 tons that it was
delivering over the target, it would certainly have been able to
return at a much higher altitude than it went in.

Only if they had enough fuel left to burn up in a climb. We rarely did.


Arthur Kramer
Visit my WW II B-26 website at:
http://www.coastcomp.com/artkramer

In article , Guy Alcala
writes
In short, design and equip them
to do the same job and they'll do it with payloads within a couple of hundred
pounds (either way) of each other. The whole Lanc vs. B-17 argument is just
ludicrous.

The crucial point though, is that you're assuming the Lanc would have to
follow US practises and fly in the big box formations. Whilst this may
have suited the B-17 with machine guns sprouting everywhere (although I
don't think it was appropriate before P-51D escorts were available), it
may not have suited the Lanc. You simply can't enforce US practises on
UK types in an attempt to 'equate' them with one another.

One Halifax squadron removed the nose and mid-upper turrets, armour,
flame dampers and various other bits, the lighter weight and less
restricted engines flew higher, faster and their losses were reduced
significantly.

--
John

On Wed, 23 Jul 2003 14:00:12 +0100, John Halliwell
wrote:

The crucial point though, is that you're assuming the Lanc would have to
follow US practises and fly in the big box formations.

Standard RAF practice was to tighen up daylight formations around
three-plane elements in vics. This was not as tight as a USAAF combat
box, but under a heavier fighter threat it probably would have evolved
further in that direction.

Whilst this may
have suited the B-17 with machine guns sprouting everywhere (although I
don't think it was appropriate before P-51D escorts were available), it
may not have suited the Lanc. You simply can't enforce US practises on
UK types in an attempt to 'equate' them with one another.

Close formation flying both increased the concentration of the bomb
pattern and the effectiveness of return fire from the gunners. The
RAF were extolling this in 1939 with Wellingtons over Heligoland
Bight, and continued to do so in "large-scale" daylight ops (e.g. the
Lancasters in the Augsburg raid).

One Halifax squadron removed the nose and mid-upper turrets, armour,
flame dampers and various other bits, the lighter weight and less
restricted engines flew higher, faster and their losses were reduced
significantly.

This works at night, where difficulty of interception is the primary
defence. It would have been a lot less effective when some measure of
resiliance and defensive capacity was required, which is why the RAF
stuck self-sealing tanks, protective armour and increased armament on
their bombers after their daylight experiences in 1939. Increasing
height and cruising speed at night made it harder for night-fighters
with a marginal performance advantage to achieve an interception,
particularly within a context where there were easier targets at
slower speeds and lower height to engage first. The same dynamic
doesn't neccessarily apply in daytime, in fact loose formations and
seperation from the main body positively attract enemy fighter
attention in those circumstances.

Gavin Bailey
--

"...this level of misinformation suggests some Americans may be
avoiding having an experience of cognitive dissonance."
- 'Poll shows errors in beliefs on Iraq, 9/11'
The Charlotte Observer, 20th June 2003

"The Revolution Will Not Be Televised" wrote in
message ...
On Wed, 23 Jul 2003 14:00:12 +0100, John Halliwell
wrote:

The crucial point though, is that you're assuming the Lanc would have to
follow US practises and fly in the big box formations.

Standard RAF practice was to tighen up daylight formations around
three-plane elements in vics. This was not as tight as a USAAF combat
box, but under a heavier fighter threat it probably would have evolved
further in that direction.


More likely reverted to night bombing. Without air superiorty
over the target daylight bombing created too many losses.

Whilst this may
have suited the B-17 with machine guns sprouting everywhere (although I
don't think it was appropriate before P-51D escorts were available), it
may not have suited the Lanc. You simply can't enforce US practises on
UK types in an attempt to 'equate' them with one another.

Close formation flying both increased the concentration of the bomb
pattern and the effectiveness of return fire from the gunners. The
RAF were extolling this in 1939 with Wellingtons over Heligoland
Bight, and continued to do so in "large-scale" daylight ops (e.g. the
Lancasters in the Augsburg raid).



Which were unmitigated disasters. The Heligoland raid had 50%
losses and during the Augsburg raid 97 squadron lost 7 out of 12
aircraft. Bottom line is the .303 was worfully inadequate against
fighters armed with 20 and 30 mm cannon and unescorted daylight
raids were unsustainable.

One Halifax squadron removed the nose and mid-upper turrets, armour,
flame dampers and various other bits, the lighter weight and less
restricted engines flew higher, faster and their losses were reduced
significantly.

This works at night, where difficulty of interception is the primary
defence. It would have been a lot less effective when some measure of
resiliance and defensive capacity was required, which is why the RAF
stuck self-sealing tanks, protective armour and increased armament on
their bombers after their daylight experiences in 1939. Increasing
height and cruising speed at night made it harder for night-fighters
with a marginal performance advantage to achieve an interception,
particularly within a context where there were easier targets at
slower speeds and lower height to engage first. The same dynamic
doesn't neccessarily apply in daytime, in fact loose formations and
seperation from the main body positively attract enemy fighter
attention in those circumstances.


Sure but as both the USAAF and RAF learned the hard way
tdeep penetration daylight raids were NOT sustainable without
fighter escort. Once air superiority had been gained the major risk
came from flak and in that case a tight formation may be a liability

ISTR that during late 44/45 daylight raids 617 squadron deliberately
flew in loose gaggle of aircraft rather than a tight box as this presented
a more dispersed target for the flak.

Keith

On Wed, 23 Jul 2003 15:35:11 +0100, "Keith Willshaw"
wrote:

Standard RAF practice was to tighen up daylight formations around
three-plane elements in vics. This was not as tight as a USAAF combat
box, but under a heavier fighter threat it probably would have evolved
further in that direction.

More likely reverted to night bombing.

Of course.

Without air superiorty
over the target daylight bombing created too many losses.

No disagreement here.

Close formation flying both increased the concentration of the bomb
pattern and the effectiveness of return fire from the gunners. The
RAF were extolling this in 1939 with Wellingtons over Heligoland
Bight, and continued to do so in "large-scale" daylight ops (e.g. the
Lancasters in the Augsburg raid).

Which were unmitigated disasters.

Of course they were. The point is that the RAF when flying in
daylight, did rely on some extent to formation flying and gun defence.
This was known to be inadequate in the absence of air superiority, and
I'm not claiming otherwise.

The Heligoland raid had 50%
losses and during the Augsburg raid 97 squadron lost 7 out of 12
aircraft. Bottom line is the .303 was worfully inadequate against
fighters armed with 20 and 30 mm cannon and unescorted daylight
raids were unsustainable.

The .5in-armed B-17's suffered from the same dynamic. Given the
ranges at night were generally closer, the .303s were more effective
as a night defensive armament than by day. Even so, the main value of
a night bomber gunner was as a lookout to initiate evasive action.

Sure but as both the USAAF and RAF learned the hard way
tdeep penetration daylight raids were NOT sustainable without
fighter escort.

Of course not, and I'm not contending otherwise. I'm just pointing
out how the late-war Lanc family evolved in the operational climate of
1944-45, which was permissive enough to allow daylight bombing to be
resumed and a certain level of adaption for that role in terms of
aircraft equipment to be utilised.

ISTR that during late 44/45 daylight raids 617 squadron deliberately
flew in loose gaggle of aircraft rather than a tight box as this presented
a more dispersed target for the flak.

Formation flying in fully-laden B.1S Lancs was never a practicable
proposition - there was almost no margin of available power in hand
for formating.

Gavin Bailey

--

"...this level of misinformation suggests some Americans may be
avoiding having an experience of cognitive dissonance."
- 'Poll shows errors in beliefs on Iraq, 9/11'
The Charlotte Observer, 20th June 2003

The Revolution Will Not Be Televised wrote:

On Wed, 23 Jul 2003 15:35:11 +0100, "Keith Willshaw"
wrote:

John H.

snip

Close formation flying both increased the concentration of the bomb
pattern and the effectiveness of return fire from the gunners. The
RAF were extolling this in 1939 with Wellingtons over Heligoland
Bight, and continued to do so in "large-scale" daylight ops (e.g. the
Lancasters in the Augsburg raid).

Which were unmitigated disasters.

Of course they were. The point is that the RAF when flying in
daylight, did rely on some extent to formation flying and gun defence.

And immediately after the Heligoland mission, when it was found that the nose
and tail turrets were unable to bear to the sides where Mfighters were
deliberately making high deflection passes, the RAF added waist guns to their
Wimpeys before going over to night bombing. IIRR, some of the early 9 Sq. a/c
had a sliding hatch on the top of the fuselage with a gun deployable from it,
but this was removed in later production. As it happened, the .303 was pretty
useless when facing cannon-armed (and armored) fighters, but there was at least
some deterrent value in the tracer, and they could always get lucky.

Guy

John Halliwell wrote:

In article , Guy Alcala
writes
In short, design and equip them
to do the same job and they'll do it with payloads within a couple of hundred
pounds (either way) of each other. The whole Lanc vs. B-17 argument is just
ludicrous.

The crucial point though, is that you're assuming the Lanc would have to
follow US practises and fly in the big box formations.

No, I'm saying that _if_ you followed US practises etc., the Lanc's performance
would be within a few % either way of the B-17's. Nowhere did I say that you had
to do so, but that is the variable that is always left out of the Lanc vs. B-17
threads, so that they wind up comparing apples and oranges.

Whilst this may
have suited the B-17 with machine guns sprouting everywhere (although I
don't think it was appropriate before P-51D escorts were available), it
may not have suited the Lanc. You simply can't enforce US practises on
UK types in an attempt to 'equate' them with one another.

See above.

One Halifax squadron removed the nose and mid-upper turrets, armour,
flame dampers and various other bits, the lighter weight and less
restricted engines flew higher, faster and their losses were reduced
significantly.

And so did B-17 and B-24 groups operating by day at various times and places, and
that's my point - it's ludicrous to compare two aircraft designed and equipped for
totally different missions and claim that one is "superior" to the other, by
looking _only_ at the mission for which one of them is optimised. In the B-17 vs.
Lanc argument, this method is routinely used to 'prove' that the Lanc had a better
payload/radius than the B-17, by comparing the Lanc's performance operating singly
at night, with the B-17's performance operating in formation by day at higher
altitudes. Basing a conclusion on such an 'analysis' is a prime example of GIGO.

Guy

In article , Guy Alcala
writes
No, I'm saying that _if_ you followed US practises etc., the Lanc's performance
would be within a few % either way of the B-17's.

But why drag the performance of an aircraft down by using it in a way
that is clearly inefficient? All this discussion has confirmed to me is
how inefficient the big box formations actually were. Dragging the
performance of a heavy bomber down to the point where it is carrying a
similar load to a Mossie, whilst remaining considerably vulnerable (and
with a crew of ten), doesn't make much sense to me.

A couple of Mossies with a light load, perhaps 2,000lbs each start to
sound more and more promising. Small, fast formations may have been very
effective.

Nowhere did I say that you
had
to do so, but that is the variable that is always left out of the Lanc vs. B-17
threads, so that they wind up comparing apples and oranges.

The B-17 bomb bay was not the best arrangement for carrying large loads.
As such had it been used in night ops, the range/payload may not have
been able to be improved to compensate for lighter fuel (or fewer
guns/crew) loads. On that basis, it's easier to drag the Lanc down by
hampering it with US practises than boost the B-17 by using RAF
practises.

--
John

John Halliwell wrote:

In article , Guy Alcala
writes
No, I'm saying that _if_ you followed US practises etc., the Lanc's performance
would be within a few % either way of the B-17's.

But why drag the performance of an aircraft down by using it in a way
that is clearly inefficient? All this discussion has confirmed to me is
how inefficient the big box formations actually were. Dragging the
performance of a heavy bomber down to the point where it is carrying a
similar load to a Mossie, whilst remaining considerably vulnerable (and
with a crew of ten), doesn't make much sense to me.

Who says it was inefficient, under the prevailing circumstances? Clearly, the RAF
heavies would have suffered much heavier losses than U.S. heavies if they had tried
to operate by day, in formation, in the same time frame (especially before air
superiority had been won). Out of formation, they would have been slaughtered on an
even more routine basis than the U.S. heavies were, because they had no effective
daytime defensive armament, lacked armor, altitude performance, co-pilots etc. etc.
And they would have been knocked out of formation much more easily, lacking all the
above.

A couple of Mossies with a light load, perhaps 2,000lbs each start to
sound more and more promising. Small, fast formations may have been very
effective.

Small 'formations' for point targets, sure. For large industrial targets covered by
smoke and clouds, almost certainly not. A Mossie could carry at most 6 x 500 lb.
bombs (2 external), while a B-17 could carry twice that internally, i.e triple the
bmb load you recommend. If the Mossie's extra speed prevents more intercepts and it
can bomb from a lower altitude, it may well be more efficient than carrying more
bombs and dropping from higher up, but it's by no means certain that's the case
(unlike some on the NG, I don't rule out the possibility, but the only way to find
out for sure would have been to actually try it, and that didn't happen).

Now, could a B-17's performance be improved by removing some or all of the defensive
armament? Sure, which was done starting mid-44. At first, they removed the radio
room gun and left one of the waist gunners behind; less ammo was usually carried as
well. By 1945, one combat wing ordered one of its groups to remove the ball turret
from their a/c, another group the chin turrets and the third group both waist guns
(and their gunners). A different group in '45 was given permission to remove the
chin turret, ball turret AND either both waist guns or the top turret (forget
which). It boosted cruise speed by about 25 mph, or allowed a tradeoff of fuel,
bombload, and/or height. But it was possible (and made sense to do so) because by
then the fighter threat was rapidly shrinking. Defensive armament doesn't help
against flak, which was the primary threat in that period, but speed and altitude
do.

Nowhere did I say that you
had
to do so, but that is the variable that is always left out of the Lanc vs. B-17
threads, so that they wind up comparing apples and oranges.

The B-17 bomb bay was not the best arrangement for carrying large loads.

Certainly (the same was true to a lesser extent with the B-24), but that was due to
the structural design decisions made, not an inherent effect of design for day vs.
night bombing. Just look at the B-29 and B-36. I don't know why U.S. heavy bomber
designers pre-war went for short and tall bomb bays rather than long and shallow
oones like the RAF's; FAIK it was considered to give a better bomb pattern, or maybe
there was some different reason. It certainly wasn't universal among U.S.
bomber/attack a/c, as I can attest having had to slide over the wing spar (just like
a Lanc) to go from fore to aft in a P-2 Neptune.


As such had it been used in night ops, the range/payload may not have
been able to be improved to compensate for lighter fuel (or fewer
guns/crew) loads. On that basis, it's easier to drag the Lanc down by
hampering it with US practises than boost the B-17 by using RAF
practises.

The question is, what was the typical load actually carried by Lancs? In 1943, it
was about 8,000 lb. (effective bombload was something like 7,450 lb. The difference
represents aborts and a/c shot down before bombing ). In 1944 and '45 it increased,
both because there were more short-range tactical missions (to more lightly defended
targets), the defenses were lighter, and because friendly terrain was closer
(allowing more fuel efficient flight profiles and more divert possibilities if low
on fuel, i.e. less reserve fuel needed to be carried). Can a B-17 carry 8 x 1,000
lb. bombs in the bomb bay? There seems some question about that - it could
definitely carry 6 (the B-24 could carry 8), and could carry a pair externally.
Could a British heavy carry more individually larger bombs internally? Yes (with
the possible exception of the Stirling), but again that was a design decision, not
an inherent effect of the type of bombing to be done.

Guy