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Old July 18th 04, 02:43 AM
Guy Alcala
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Chris Mark wrote:

From: Guy Alcala g_alcala@junkpostoffic


Chris, could I know the source of your loss rate figures?


Part of a project I'm working on. I've been plugging away at a history of the
air war in the MTO off and on for some years and got curious about operations
in other theaters and how they compared.


Can you break out B-25 and B-26 losses in the MTO excluding North Africa? Those
are the onesI'm really interested in. BTW, I take it theseare all combatlosses and
don't include operational losses?

Whether B-25 or B-26, losses track pretty closely with mission profile. For
example, the 319th, a B-26 group sent to the MTO, was trained in low-level
attacks. But after less than three months, losses were so severe that it was
withdrawn from combat and retrained in medium altitude bombardment, after which
losses plummeted. The 310th, a B-25 outfit, was somewhat similar, although it
kept a specialized low-level squadron for sea sweeps for a long time.
Whether B-25 or B-26, used as medium altitude bombers, losses were in the
roughly one per 150-200 sortie range and 3-4 times higher when they went down
on the deck.
B-26 losses were higher than B-25 losses in the MTO. I suspect the biggest
reason was better single-engine performance by the B-25.


I'd agree, although engine maintenance would have also fed into the problem. Given
the maintenance problems, losing _an_ engine might well lead to loss of the
airplane just from failure of the other one due to overstrain, even if it was
otherwise controllable on a single. the other thing I wonder about is if the B-25
had better air filters at the time. I know many of the early B-26 groups in North
Africa retrofit the larger intakes (for air filters) on the nacelles of their early
B models, but I don't know how the B-25 setup compared at the time.

B-26s also had much higher abort figures than the B-25, several times higher,
in fact. I suspect better reliability and easier maintenance of the B-25s
Wright engines, played some role in this, but more important likely was the
problems the B-26 had with its electrically operated props, so that a generator
failure would lead to a mission abort.


No doubt about it. There was also an issue, in the PTO at least, with prop tip
clearance while taxying on soft ground/runways. The difference between the B-25
and B-26 was only 3 inches, but that was apparently enough to cause problems. The
B-26B-4 and subsequent were given an extended nosewheel partly to compensate for
this (and also to improve the wing aspect angle on takeoff), and later the B-26F
and G models (Art flew a G) also had the wing angle of incidence increased to 3
degrees, providing similar benefits to takeoff performance and proptip clearance.

It also seems that it was far easier to make repairs on the B-25's fuselage skin,
given that it was mostly flat panels instead of the B-26's double curvature. And
as Art will tell you the B-26's nose gear was rather weak, which didn't help its
mission capable rate when operating from rough strips.

Conversely, in the Pacific, with the B-25 groups flying low-level missions, the
hydraulicly operated props caused losses. Typically, a plane would take a hit
in the oil cooler and start losing oil. Had the plane been at 10,000 feet,
that engine's prop would have been feathered and the engine shut down. Good
chance the old bird would make it home or to an emergency field. But on the
deck shutting down the engine was not an option. The plane had to maintain
power on both engines until it got clear of the target. Unfortunately, by that
time, oil pressure might well have dropped so low that the prop couldn't be
feathered.


The B-25 had good short field performance compared to the B-26. That made it
more desirable in the rougher theaters of operation. Turnaround time on the
B-25 was quicker as well, so that it was possible when needed, say as during
the Anzio invasion, for a single plane to fly multiple sorties in a single day.
Maximum lifting capability was around two-thirds greater (depending somewhat
on models compared) for the B-25 compared to the B-26, basically meaning that
B-25s could stagger into the air with seemingly impossible loads. Thus, in the
Pacific, you would have B-25s staging out of Palawan flying missions to bomb
shipping in Saigon, staying in the air 10 or 11 hours.
All the B-26 units in Italy were eventually phased out, as they had been in the
Pacific, so that eventually B-26s only operated in the ETO.


I know one US MTO B-26 Group was briefly converted to B-25s before relocating to
the states for transition to the A-26 and the PTO, but I thought the other 2? (3?)
remained in the theater. ISTR the various allied air forces flying the B-26
continued flying it in the MTO, although at least a couple of the French groups
moved to France after Anvil/Dragoon. I remember seeing a photo of one US B-26 base
on either Corsica or Sardinia, which had six parallel packed and oiled dirt
runways, giving some idea of the dust problems in theater.

Guy