Short Stirling used as Maritime Patrol Aircraft for Battle of Atlantic?

The quick answer is no for reasons to do with the U boat war and the aircraft available.

There is no mid Atlantic Gap early in the war. Its a consequence of increasing escort and aircraft range from the UK and Ireland and Canada/US and Iceland and the Azores and Gib making the mid Atlantic the only place a U boat could operate that was not an elaborate form of suicide.

Short form of what happens is this. When a ship enters or leaves port you know where it is. As soon as it leaves port it can disperse across the ocean until it concentrates to enter a port ( same applies if you want to hunt U boats). So in terms of finding shipping you want to operate as close to a port as possible so you can find things. You also do not want to attack ships in convoy ships in convoy have escorts who shoot back. That's the other way you can hunt U boats. Also the biggest source of targets is UK coastal shipping which is easy to find, vital and also escorted by and sea and air.

Progressively the number and quality of the escorts increases, air and naval and they spread both the number of convoys the number of escorts and the air coverage further and further out.

Its not until September 41 that attacks on ships in convoy exceed attacks on unescorted ships - of which there a lot, either because the captains choose to and a non British captain can so choose. Because they are so old and slow they can't keep station and are carrying lumber, or because of an engine casualty forcing them out of convoy.

That then stops until about Feb/March 43 - mostly because of the number of targets unescorted with lights at full brilliance off the US coast.

And by then the U boat losses exceed replacement rates. Throughout the war 85% of sailings to Britain are never attacked at all.

So the Stirling. The Stirling is as said a multi purpose aircraft specced in 36/7. Its range when loaded is about 600 miles and there are some issues with the bomb bay. So it could be used as an MPA with some adaptation. BUT so can the Hudson, which has fewer crew and engines and the same range more or less and is the chosen MPA early war. Same with the Wellington. Catalina and Sunderland are better with more range more stores more dakka generally.

The limiting factor on over ocean flying is the quality of the crew to navigate and keep things working over many hours so there is probably a practical limit to the number of crews you can have flying. These are also the guys you want in Pathfinder force and things like 617.

Up to 1943 Stirling is probably best used as a bomber. But then with Halifax and Lancs coming on in numbers its a 4 engined bomber with the capabilities of a 2 engined bomber and some utility as a transport, special ops platform. There is nothing it can do that can't be done at least as well by a Wellington, Beau, Mosquito, Swordfish, Cat, Sud. None of which can tow gliders.

Basically for the range and load characteristics the Wellington is a better platform except as a tug or transport.
 
While the techical descussion is very interesting, what has to be done to actually see Stirlings used by RAF Coastal Command? What has to happen for such an an action to be taken, in regards to the various commanders involved how will they work it out between them? How long would it actually take for the aircraft transfer to actually take place and to have the aircraft suitably modified for CC use? WRT crews, how long until crews are sufficiently trained on the new type for them to enter service?
 
While the techical descussion is very interesting, what has to be done to actually see Stirlings used by RAF Coastal Command? What has to happen for such an an action to be taken, in regards to the various commanders involved how will they work it out between them? How long would it actually take for the aircraft transfer to actually take place and to have the aircraft suitably modified for CC use? WRT crews, how long until crews are sufficiently trained on the new type for them to enter service?

The problem is its not suitable. the range crashes when the aircraft is loaded to about the same as a Wellington loaded. Essentially its a muti function aircraft used as a stop gap until production of Halifax and Lanc pick up then its used for its non bomber functions. In 1943 it has double the number of engines, for the same general performance as the Wellington, and the engine is also used by the Beaufighter and the Halifax. The Wellington can do just as well on two engines and its power plant is used by the Swordfish and Sunderland both of which you can only have in small numbers for unrelated reasons.

If you want to shoot at things and generally similar ranges, use the Beaufighter as God intended.

Could you convert it, probably but why? For long range work, much longer than the Stirling could ever manage the RAF has Liberators from 41. These are not really suitable for combat over Germany but can carry a weapons load, ASV radars and other kit like long range fuel tanks.

And thats what you would do, add fuel, add an ASV radar and tootle along with the Hudsons, Whitleys Wellingtons and Liberators. And not tow gliders deliver stores and spies to the resistance, transport folk around

Nothing really wrong with the aircraft its really a British version of the SM Marsupiale types
 

Garrison

Donor
The thing is that Shorts already made a superb maritime patrol aircraft in the shape of the Sunderland Flying Boat. Probably more likely that if they decide they want more patrol aircraft they step up the Sunderland production, with the Stirling temporarily pressganged into service.
 
An MPA variant Stirling is probably going to impact on Sunderland numbers, considering the commonality between the two designs. It's going to require fewer resources per unit to acquire, which will mean, considering the capability of the design, Coastal Command will prefer them over the expensive Flying Boat.
I would actually argue for the opposite: Coastal Command will take the Stirling as a stopgap measure, but only until enough new Sunderlands are available. The ability to land on water instead of special ultra long runways is too much of a boon for them.

I can however see the new model Sunderlands being designed around some of the attack and screening procedures that were pioneered by the CC Stirling and proved to work well. So expect different bomb bays, armaments or even small changes like cockpit layout or crew accomodations.
 
You don't have to build more Sterlings right now, just convert what you have to use them as a Long range Maritime Patrol aircraft. Take off what you don't need or want, add things like the extended tanks, more windows to look out of, cut the armament down and fix what you need to do about the dropable ordance you are using. You don't need a quad turret in front, fair it off and have a pair of 20mm Hispanos fixed and fire by the pilot, then put a glass fairing where observers can look out under the aircraft up front and on the sides of the fuselage. You don't need the rear turret unless you are going to be going in the Bay of Biscay and even then if you are doing night missions the German's won't move night fighters to cover the UBoats in transit at night. Fair off the back and have an observer back there with a way to shoot out flares or smoke buoys to mark something if they see it for a new pass
 
The Air Ministry and the Treasury would have been better off issuing separate specifications for both a four engine bomber and a four engined transport aircraft. Even today's airforces maintain separate specifications for those roles.
Well, most of them do, at least in theory. But have you ever noticed how many Russian transport aircraft have windows on the underside of the nose? That's so they can be converted to bombers more easily by building-in a bomb-aimer's position. It's also worth noting how many transports get pressed into service as bombers in various third-world conflicts, even if they're just dropping barrel bombs out the back. And then there's the US with its AC-130s and armed Blackhawks, and good old NZ using P-3s and P-8s as transport aircraft to various Pacific islands, and so on. It turns out there's a substantial degree of overlap even now.
 

Errolwi

Monthly Donor
good old NZ using P-3s and P-8s as transport aircraft to various Pacific islands, and so on.
But there were no design compromises in using MPAs to drop stuff off while they are there. I saw a bunch of formal silverware in a P-3 once - if you are going there anyway and you can pass it out the door, why not?
There was a lot of fear in the 1930's of hiding bombers as transports.
 
There was a lot of fear in the 1930's of hiding bombers as transports.
Which was entirely justified. A large number of bombers started out as transport aircraft.

Douglass B 18
Dornier Do 17
Focke Wulf FW 200 Condor
Heinkel HE 111
Savoia Marchetti SM 79

Even the Short Stirling is ultimately a development of the Short C Empire flying boat and let's not forget the Luftwaffe's first heavy bomber the Junkers JU 52/3m
 

Coulsdon Eagle

Monthly Donor
Which was entirely justified. A large number of bombers started out as transport aircraft.

Douglass B 18
Dornier Do 17
Focke Wulf FW 200 Condor
Heinkel HE 111
Savoia Marchetti SM 79

Even the Short Stirling is ultimately a development of the Short C Empire flying boat and let's not forget the Luftwaffe's first heavy bomber the Junkers JU 52/3m
More truthful that many bombers were designed under the cover of a transport or airliner. How many passengers could fit into the Flying Pencil?
 
Back to the Sterling's range. There was a trade of between a large weight of relatively small bombs (2000lb max per bomb) of 14,000 lb which limited the range to around 550miles, or a much longer range, some sources say around 2,000 miles but with a reduced bombload of 3,500lb. So you are trading bomb load for fuel, that is a fairly easy concept to follow. A Long Range Maritime Patrol Aircraft requires endurance and range rather than a huge bomb load, Therefore if 3,500lb of ordnance is sufficient for the task then the maximum range can be exploited. An advantage of using the Sterling as a LRMPA is that strait out of the factory it had many of the essential attributes for this role,
Previous posters have suberised those Range will be reduced as you load the aircraft up with more equipment especially drag inducing things such as ASV1. However removing draggy items such as the mid upper turret could well mitigate this.
IMVHO, a Sterling LRMPA in service in the winter of 1940 Patrolling well out into the Atlantic could well have reduced the losses of independently sailing merchant ships, by making it signifigantly harder for the U-boats to give chase on the surface, HYMMV.
 
I think I would take Stirlings as a stop gap until you could get me more Sunderland or Liberators. Convert them, pull out the stuff you don't need, bang in more fuel tanks and get cracking.

The big benefit is making it harder for U boats to operate on the surface and/or break contact with convoys they have sighted. Obviously if you can sink them so much the better but driving them away is enough on the day.
You don't need the rear turret unless you are going to be going in the Bay of Biscay
You may as well leave the rear turret - useful to give the U-boat a bit of spray on the way past - keeps the crew heads down rather than shooting back.
 
The Stirling had a large cargo/troop capacity in the fuselage as part of the specifications. Hence the Stirling MkV transport version.

This could allow for fuel overload tanks to be fitted in the fuselage without centre of gravity issues so the potential range is more than the listed wing tankage and bomb cell overloads of the manuals.

One might note that both the Whitley and Wellington could be fitted with internal fuselage overload tanks (the same type IIRC) and were so it is not something novel. The limit might be the overall loaded weight for the available runways. So part of this overload tankage process might be extending runways for a longer take off run.
 
think I would take Stirlings as a stop gap until you could get me more Sunderland or Liberators.
I don’t know. I think it may actually be better than either for the role.

If you take a Stirling, remove the dorsal turret (or the retractable ventral turret for the Mark I) and add observation blisters where the Mark II had .303 side ports, put 250 lb depth charges in the wing cells and 500 lb depth charges in part of the bomb bay, take the rest of the bomb bay for fuel, fly it low (around 5000’) and slow (probably with one engine feathered in cruise) and you will have a very long range aircraft. Longer range than the Sutherland and probably not far less than the Liberator. And with its extremely good maneuverability, particularly at low altitudes, and its ability to basically drop a spread of depth charges between the wing cells and bomb bay, it will likely be better than either at killing U-boats. Though about equal in deterring them.

It would be less well armed than the Sunderland, so that would probably be preferable over the Bay of Biscay (not that the Stirling couldn’t go there, it would just have less guns to use) and it requirement for a long runway would mean the Sunderland would be preferred wherever such infrastructure didn’t exist. It would probably still be beaten out by the Liberator in range but could carry a much bigger, and better placed, load of depth charges. So I expect it would operate alongside them later in the war.

All in all, I think the Stirling has a lot more potential in the LRMPA role than its being given credit for.
 
The Air Ministry and the Treasury would have been better off issuing separate specifications for both a four engine bomber and a four engined transport aircraft. Even today's airforces maintain separate specifications for those
Agreed, wonder if Shorts warned of the likely consequences of mixing the needs.
 
would you be able to mount a retractable mount for some RP 3 rockets with the 60lb SAP head? Between having a pair of Hispano 20's in the nose and the ability to fire some rockets on the run in before releasing the depth charges might make the Uboats less likely to try and fight it out on the surface. ALso what about something like the Leigh light mounted onboard the AC for night use as things get on?
 
While the techical descussion is very interesting, what has to be done to actually see Stirlings used by RAF Coastal Command?
The best route would probably be an earlier Butt Report and Tizard/Blackett winning out in the subsequent bun fight. So it is accepted that Bomber Command is not hitting much and that the main benefit is distracting/tying up German resources in air defence, that means a much smaller 'main force' for Bomber Command, at least until they get better accuracy, electronic aids, etc.

In that scenario it is easier to argue for the transfer of aircraft from Bomber Command to Coastal Command. There are also knock on benefits for all the other services of not pouring so much resource into Bomber Command, but that's a bit beyond scope.
What has to happen for such an an action to be taken, in regards to the various commanders involved how will they work it out between them?
It will take a direct and clear order from above for the RAF to do this, at least Air Ministry level if not Cabinet/Churchill.
How long would it actually take for the aircraft transfer to actually take place and to have the aircraft suitably modified for CC use? WRT crews, how long until crews are sufficiently trained on the new type for them to enter service?
Finger in the air I would say a couple of weeks for the first trial fit. There is space and the Stirlings Flying Boat heritage probably helps in this case. Subsequent aircraft should be a lot faster.

Crew wise I would think it is easier to re-use the existing Stirling crews, at least initially. In theory they've already been trained in long distance navigation over water and they know the aircraft. Refresher course on navigation for the pilot/engineer, the gunners get a short course in observation/spotting. Squeeze that in while the aircraft are being refit then off they go.
 
Top