Bombers, speed over defensive armament, why were lessons ignored ?

Could we make a little effort to understand what each other are saying? Here is mccoffee's comment; I invite him to correct me if I have misinterpreted him:

that [the Mosquito] could carry a 4000lb bomb load to Berlin while outrunning fighters, is fantasy. Yes, it could carry the load to Berlin, but it could not run from fighters until it shed its load.

There are ample references to Mosquitos dropping cookies on Berlin and other cities; the point is that neither they nor any aircraft could top out in all aspects of performance simultaneously.

 

Are you suggesting bombing would have been more efficient/safe if only Mosquito's/ light fast bombers were used? Send, 2000 Mossy's to bomb an oil refinery? You think that'd be successful? What would you do, send them 1 at a time? If not then you'd have a large bomber formation, just like the heavies. They would be destroyed just as easily as the heavies minus the hundreds of guns in the box formation that would allow some defense. Would they be successful? Less success would be my guess.

 

Poppy, I think someone indeed noted that up the thread....and of course Bomber Command could have all the same issues with maintaining/housing/flying of such a force; there's only a slight economy of scale when it's two engines to be serviced instead of four, for example - the aircraft has to be pulled off roster, not just its engines

And carrying its maximum bombload to Berlin or wherever....at least the Lanc has four-engined redundancy in the case of engine issues or damage; loose one engine for whatever reason, it carries on - but the Mossie doesn't. It is running under the same vulnerabilites to mechanical failure, damage etc. as any of the early-war two-engined "heavies".

 

The original post is clearly about using higher-speed aircraft - Mosquitos, stripped-down Lancasters, or some hypothetical type - in lieu of the standard heavy bombers in the RAF's night bombing campaign. Formations were only really useful - or feasible - in daylight, when defensive armament was also more relevant.

As it happens, I think the B-17s could have benefitted from swapping a few guns and gunners for more payload - not that I'd want to try to convince the crews of that! - but even with fighter escort an inner layer of defense would be necessary.

 

Could this actually be done? I read once that its two-cell bomb bay design was mandated by the layout of the airframe members...and there was nowhere to extend the bomb bay to.

8,000lbs was its maximum bombload; this had to be reduced for longer-range raids, a bit like (tho' thnkfully not as much!) as Bomber Command Stirlings being able to reach down to Turin, but only carrying a fraction of their bombload...

Was its fuel load ever extended? Or was it at it's maximum physical limits inside the airframe too by the matured "G"?

Like all aircraft - more powerful engines would allow more payload to be carried - but could the B-17 handle the stress factors of the more powerful 1,400-1,500 P&W installations without undue strengthening?

It's perhaps worth noting that when the B-17F was uprated to the few YB-40 "bomber escorts" - one of the things that HAD to be traded for extra guns and ammo was....fuel.

 

The fact that it had a low radar signature wasn’t a design plan, nor was it completely because of the mostly wooden construction. There were a combination of things which made the "Mossie" pretty tough to pick up on the rather rudimentary radar of the day.

Using ferrous metals only for the engines in main, they also used tens of thousands of brass screws as reinforcement at many points, brass is both non-magnetic and has a low radar return quality. These were serendipitous events, not designed qualities. If I recall one of the early documentaries on the de Havilland DH 98, the design team drew an outline of the engines and needed fuselage size for two crew members and a bomb bay capable of carrying the load of a medium bomber. They then drew the smallest possible outline of airframe possible around these three necessities that would produce an aircraft capable of flight.

This design method truly reduced the "size and shape" of the plane to a minimalist approach, providing speed and low cost of production. One must also remember that the fact that it turned into one of the finest multi-purpose planes of the war, it was designed to be a faster bomber to replace the Blenheim (I think) medium which had been around for a long time.

 

phylo, I think you're confusing the -17 with the -29; that had two bomb bays separated by the main wing spar, and they had to do some serious alterations to fit the 'Silverplate' version to carry one large (atomic) bomb.

Oddly enough 8,000lb is what I was thinking, vice the usual 5-6000 on missions to Germany. The bomb racks as built could hold eight 1000pdrs (or six of the rarely used 1600lb bombs). Suppose you delete the waist guns and gunners; that's about 1000lb*, which unless there's something I'm missing should allow one to carry another 1000lb of bombs, especially since you only have to carry them one way. The ball turret only scored about 5% of kills (USAAF study posted I believe by mccoffee on the old History Channel site); some B-24 groups deleted it, sometimes mounting a .50-caliber in the opening. The chin turret also added weight and drag; ironically it came into service about the same time that the B-17s got fighter escorts, the real solution to the problem. If the guns were no longer the primary defense, I'm thinking the single nose .50 and the 'cheek' guns might suffice.

Whatever was removed would be swapped for an equal weight of bombs, takeoff weight would be the same, so there should be no penalty in performance or fuel use.

* .50 cal MG about 60lb; 500 rounds, belted, 150lb (per gun) plus the flexible metal ammo chutes; the gunners, their gear, their share of the plane's 18 oxygen tanks.

The maximum load of the B-17 was 17,600lb, 6x1600 plus 2x4000 on underwing racks. Never heard of it being used, and it certainly wouldn't fly very far!

The YB-40 had particular trouble keeping its place in formation on the homeward leg, when everyone else had dropped bombs and it still had all those guns.

 

a couple things of note

for the Mossie it was picked up as soon as the squadrons took off from English A/F's by sophisticated LW listening devices placed all over the Reich, and it was not at all immune to German ground based or LW air to air radar systems...........more in my book to come. simplification for the Mossie crews was just to drop off all radar/radio electronic transmissions and fly with "eyes" only as many of their counterparts did even in 1945 when 95 % of the LW airborne radar systems were rendered useless by Allied jamming.

for the B-17 the arms arrnagements would depend on the LW attack tactic as in spring of 44 it was found much easier to attack in wedge/staffel strength from the rear on B-24/B-17 formations and had not US P-51 escorst be inplaced the US bomber formations would of ceased to exist with horrific losses. defending oneself with a single or twin .50's just does not do the job of protection.

 

C., this is what I meant -







"Bifurcated" is perhaps a better definition than "two-cell"...each door revealed one side of the divided bay.

 

Way to make your point Pi. Very nice. Cheers.

 

Thanks, Carronade. I wasn't sure if I was being unclear, or if there was just a refusal to 'hear'.

Removal of some of the guns from mid-1944 on isn't a bad option, and as noted, some of the 2nd Air Division B-24 groups did remove the ball turret. I'm going to attach that document below.

It is also correct that both the B-17 and B-24 carried 5-6000 lb loads rather than their maximum rated loads on long distance missions. For the ultra long range TIDAL WAVE mission, the load was 3500 lb(from memory without looking it up), trading fuel for ordnance.

The YB-40 program failed because of its weight disadvantage once the rest of the formation dropped their loads.

As Poppy notes, a large daytime Mossie formation in the period before Allied air supremacy would be a massacre. After Allied air supremacy, the heavies are more efficient anyway. In a nightime RAF bomber stream, the streams time over target becomes much longer and the operational aspects of getting the much greater number of aircraft out of and back into their bases at night becomes much more complicated and dangerous due to airspace congestion.

 

I have Galland`s autobiography and have read it a few times. Unfortunately it doesn`t have an index*, at least my copy doesn`t, so quoting passages is difficult.
However I remember for a fact he was very impressed with the Mosquito and how difficult it was to shoot down. It`s interesting that you seem to say he was wrong about its radar signature being no smaller than any other plane.

*Do any copies of his autobiography have an index ? If not I think this is a serious omission in my opinion. Has anyone researched an index for it ? If they have how can I get one ?

 

I`m not suggesting that Mosquitos (is it Mosquitos or Mosquitoes ? ! ? ) bombed during the day.
My whole aim in this would be to minimise aircrew lives lost, and as a secondary advantage, shot down planes. That would even be at the cost of fewer bombs dropped, certainly on one target at the same time.
As an aside, smaller raids more frequently would mean more sleep lost for German workers, and hopefully a consequent negative effect on productivity, but possibly (and positively in my view), fewer civilian deaths.
What`s not to like?

 

There’s a number of factual errors and erroneous assumptions about the Mosquito in this thread. I don’t intend to become embroiled in comparative woulda coulda shoulda discussions, beyond the fact that, after two years and an enormous industrial effort to build up a four-engine heavy fleet, Bomber Command wasn’t going to pull a Mosquito force out of thin air.

There’s been some question as to Mosquito loss rates over Berlin. During the Battle of Berlin, between November ’43 and March ’44, Mosquito losses over the Big City ran at 1.1%, versus 5.5% for the heavies. These were bomber sorties, from the Bomber Command War Diaries site, which gives separate total for Mosquito night-fighter patrols under the auspices of Bomber Command. They weren’t Pathfinder sorties, as the limitations of Oboe did not allow 105 and 109 Squadrons to reach Berlin, following a decision by their Airships not to proceed with the Oboe repeater system, apparently believing (in error) that H2S in 8 Group heavies would enable the desired concentration of bombing over Berlin. H2S wasn’t fitted to 139 Squadron’s Mossies until late March ’44.

Mosquitos over Berlin took even lower casualties later in the war. Between January and April 1945, there were 3,695 successful sorties by Mosquitos to Berlin. Fourteen Mosquitos were lost in action on sorties to Berlin, despite jet and conventional fighters, and the ever-present flak, for a total loss rate of 0.38%. Of the total successful sorties, 1,459 were by ‘cookie’ Mossies, which dropped 4,000 lb bombs. Eight of the losses were cookie Mossies (including one lost in a collision), loss rate 0.55%. So the idea that the Mosquito couldn’t successfully take a 4,000 lb load to Berlin doesn’t stand up to scrutiny.

I’ve done a quick graph of Mosquito night losses versus losses incurred by the heavy force, also at night. Source for sortie numbers are Sharp & Bowyer for Mosquitos, Middlebrook for the total force, losses from Middlebrook, Bomber Command Losses and Air Britain serials.


Also a graph of Bomber Command’s loss rate versus sorties undertaken. Lines indicate loss rates by month and cumulative, for both forces. Source is Middlebrook.


As the question’s been asked, I’m also attaching a graph I did of comparative loss rates between Bomber Command and 8[SUP]th[/SUP] Air Force. Source for 8[SUP]th[/SUP] Air Force is Richard G. Davis work, which until recently was available in Excel form listing sorties and tonnages by raid for the 8[SUP]th[/SUP], 9[SUP]th[/SUP] and 15[SUP]th[/SUP] Air Forces, along with Bomber Command and 205 Group.


Also as the question’s been asked, I’ve used Davis’ numbers to do a graph of 8[SUP]th[/SUP] Air Force versus Bomber Command losses against targets in Germany.


Bomber Command never seemed to have any trouble finding pilots and engines for the heavies, despite their having loss rates several times higher than that of the Mossies. All that’s woulda coulda shoulda though. An enlarged Mosquito with two Sabre engines and an 8,000 lb bomb load was discussed in late 1941, but didn’t come to anything, at least partly because the cookie Mossie was developed.

Edit - Made changes to title on first graph, should be clearer.

 

Well mhuxt, I think that`s very very interesting, and, more importantly, goes to show how bleedin` brave those BC aircrew were.
Personally I think it`s scandalous that they never received a campaign medal, though I also think it scandalous they were ever asked fly missions at such loss rates in the first place.

Incidentally, does anyone know how fast a simplified cleaned up Lanc with no defensive armament and possibly a smaller bomb load, would be ?

 

Yes, you're quite right about the bravery involved. It's a good thing no-one ever tried to make a soldier out of me, I'd have been a greater threat to my own side..

The graphs above should be taken for what they are, quick Excel-fu jobs on sources I had to hand, some of which I did a long time ago, some of which I did yesterday. I drew on a variety of sources, who will have had their own methods of counting, etc. So, what I:m saying is don:t shoot the messenger (yet). I'll go back in ahd try to provide more info re; sources and assumptions. Off the top of my head, one of the Middlebrook graphs may include crashes on return, the other not, but I'll check.

My folks grew up in England during the war, and had the same things to say about the gallantry and generosity of US personnel as do many of the ex-servicemen whose memoirs I've read. That against a backdrop of sometimes sever losses, says a great deal.

 

For what it`s worth I think crashes on return from ops should be included, if possible.

 

That's Bomber Command sorties, both day and night, with loss rate based both on failed to return and crashed on return. Source numbers are from Middlebrook.

Davis' numbers for the 8th Air Force don't provided any distinction on failed to return / crashed, so can't do this for 8th AF. Would have to go through my Mossie data and attempt to determine operational crashes from non-ops, would take time.

Wanted to get Excel to stack day sorties on top of night sorties and include the total loss % line, wouldn't do it, so FYI here's how BC's sorties break down by day and night. Source is Middlebrook again.

 

Excuse my ignorance, but what does TTL mean ?

 

Hiya. Sorry, "TTL" = "total", as in both failed to return and written off on return, just me being lazy with Excel.