Short Stirling

[PR19_Kit]

I know about the ultra-restrictive bomb-bay design etc. but why was the Stirling such an under-performer in service?

Every raid report that flew Stirlings is peppered with comments like '....we struggled to reach a high anough altitude to clear the Alps...' and '.....the enemy nightfighters could easily climb well above us and then dive from the cloud cover, while we were silhouetted against the bright sea scape....' etc.

All of which indicates that the Stirling was under-powered, over weight or didn't have enough wing area. But it was larger than a Halifax or a Lancaster, it had 4 x 1375 bhp Hercules engines against the Lanc's 4 x 1280 bhp Merlins, the Stirling's wing area was 1322 sq. ft. against the Lanc's 1300 sq. ft. The Stirling was admittedly quite a bit heavier than the Lanc, 44000 lbs against 37000 lbs empty weight for the Lanc, but would that make it as much of a dog as it seems to have been?

[Alvis 3.14159]

Bill Gunston covers the Stirling in his book "Plane Speaking", a  nice publication that explodes many of the myths of aviation. The 99' wingspan is usually blamed for the lack of performance, yet the Halifaxes and Lancasters were only slighty wider. Turns out the airfoil shape itself was the reason it didn't have the altitude capability later planes would have. It was designed by a flying boat manufacturer, whose experience at lower altitudes was excellent, and the requirements at time of design weren't for the higher altitude in any case. Had the war revolved around close support of the army, the Stirling wouldn't have been deemed such a pig. Of course, stooging around at lower altitudes over the battlefield in a plane as large as the Stirling would have given it a reputation more akin to the Battle....

I'm not sure if it shares the same airfoil shape as the Sunderland, but it would make sense if it did. I can't see a Sunderland being useful over Berlin..ohhhhhhhhhhhhhh, now THERE'S an idea...hmmmmm


Alvis Pi

[kitbasher]

I can't see a Sunderland being useful over Berlin..ohhhhhhhhhhhhhh, now THERE'S an idea...hmmmmm

Sunderlands were VERY useful over Berlin - during the Airlift!

[Alvis 3.14159]

Ah, good point. At least they didn't have to deal with flak and the Luftwaffe though.  A Sunderland in RAF standard night bomber marking though...hmmmm.

Alvis Pi

[PR19_Kit]

Hm, yes. I hadn't thought of the airfoil shape, but I can see it would have had some effect.

As for Sunderlands and Berlin, my Dad had to look after some of them during the Air Lift. They flew the salt supplies into the Wannsee, in the south west corner of Berlin, as their hulls were already corrosion proofed. Their servicing was taken care of by landplane 'erks from RAF Gatow, who kept dropping their tools in the Lake!  They soon learned not to after the cost of the second 'accident' onwards was deducted from their pay! 

[alertken]

Not all bad: "it could not make a decent operational height (it was a) pig (on) taking off and landing (but) in the air it was a darling - it could turn inside a Spitfire" D.Richards,The Hardest Victory,Hodder,94,P.311. The problem was deployment timescale.

Spec. B.12/36, 15/7/36 was the first for a 4-motor metal Heavy, and was intensely competed. Supermarine had large structure expertise, albeit in wood, so was awarded a prototype contract for T.316/318 (prototype lost in Woolston bombing); Short won a prototype contract for (to be) Stirling on the base of its large metal structure expertise, design and build, S.23 Empire, and use of that type's Gottingen 436 mod aerofoil section. It was that low-risk that beat bids from proven bomber designers AWA, BPA, and the winner of the 1935 Heavy twin, Vickers. Medium Spec. P.13/36 went to twin designs from Avro (NACA 23018 aerofoil section) and HP (NACA 23021) which later became 4-engined Heavies. Ministers poured much effort into volume production of Stirling, turning auto industry into aero shadows, buying in mid-38 100 Halifax/200 Manchester, and 200 Stirling from a Production Group that grew to include Short Bros/Rochester, S.Marston, Short Bros & Harland/Sydenham, Austin Aero/Elmdon, with fuselages from Jaguar Motors and other chunks from the Brockworth "A.W.Hawkesley" factory. But peak output from the Group was 79 monthly, 1943, whereas Halifax was 208 p.m, Lancaster 260, 1944. Ministers accepted AM Harris' view: Stirling Prodn Group had "virtually collapsed (makes) no worth-while contribution to our war effort in return for their overheads (should) be a wholesale sacking of the incompetents who have turned out (c)50% rogue a/c from (Harland...T)he incompetent drunk' who ran (Short.)'" Harris to RSC 30/12/42,C.Bryant, Stafford Cripps, Hodder,1997,P330. In December,1942 Oswald Short was ejected from his own Co. which was Nationalised; production phase out at S.Marston was handed to AWA.

aerofoil data: http://www.ae.illinois.edu/m-selig/ads/aircraft.html#conventional