Wild_Bill_Kelso
Senior Master Sergeant
- 3,231
- Mar 18, 2022
"Miss Shilling's orifice introduced"
Ok wut
Ok wut
March until October of 1940: fighters' ranking
- Thread starter tomo pauk
- Start date
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Wild_Bill_Kelso
Senior Master Sergeant
- 3,231
- Mar 18, 2022
Agree with your post though, the 'improved' Summer 1940 Hurricane was probably a much closer match for a 109E-3 or whatever
The biggest advantage was geography, in principle the Hurricane over UK just had to stay in the fight knowing the opponent had to break off to get home, the situation was reversed with the Spitfire V over France, getting into a turning fight didnt help the Spitfire, it couldnt break off and get home.
Miss Shilling's Orifice was a very simple technical device made to counter engine cut-out in early Spitfire and Hurricane fighter aeroplanes during the Battle of Britain. While it was officially called the R.A.E restrictor, it was normally referred to under various names, such as Miss Tilly's Diaphragm or the Tilly orifice in reference to its inventor, Beatrice "Tilly" Shilling.
Complaints from the pilots led to a search for a solution. Beatrice 'Tilly' Shilling, a young engineer working at the Royal Aircraft Establishment at Farnborough, came up with a disarmingly simple solution. She introduced a simple flow restrictor: a small metal disc much like a plain metal washer. The restrictor orifice was made to accommodate just the fuel needed for maximum engine power, the power setting usually used during dogfights. It came in two versions, one for 12 psi manifold pressure and one for boosted engines with 15 psi manifold pressure.[3]
While not completely solving the problem, the restrictor, along with modifications to the needle valve, permitted pilots to perform quick negative G manoeuvres without loss of engine power. This improvement removed the annoying drawback the RAF's Rolls-Royce Merlin-powered fighters had had in comparison to the German Messerschmitt Bf 109E machine, whose Daimler-Benz DB 601 inverted V12 powerplant had possessed fuel injection since 1937. Miss Shilling travelled with a small team around the countryside to one RAF base after another in early 1941 fitting the restrictors, giving priority to front-line units. By March 1941 the device had been installed throughout RAF Fighter Command. Officially named the 'R.A.E. restrictor', the device was immensely popular with pilots, who affectionately named it 'Miss Shilling's orifice' or simply the 'Tilly orifice'.
This simple and elegant solution was only a stopgap: it did not allow inverted flight for any length of time. The problems were not finally overcome until the introduction of Bendix and later Rolls Royce pressure carburettorsin 1943.
military-fandom.com
PS: Even engineers have a since of humor it would appear...
Shortround6
Major General
We have to be careful that we keep the planes within the time frame, a big reason were going above 600 posts.
Slaterat's post lists a lot the changes to the Hurricane but many of them were before March (like they weren't flying fixed pitch props anymore) and Miss Schilling had yet to make her contribution in Oct?
However the same is true for the 109, the 109 in March/April 109 was often not the 109 in use in October.
For the Japanese the Ki 43 was a prototype or two in 1940, not even the combat test the A6M2 got. The A6M2 also had a structual problem with the wing althtugh they didn't find that out until after Oct 1940 but did fix it well before Peral Harbor.
P-40s in the time frame had no self sealing tanks, no armor and the engines were going back to the factory to be reworked because they would not last until the desired overhaul times.
Slaterat's post lists a lot the changes to the Hurricane but many of them were before March (like they weren't flying fixed pitch props anymore) and Miss Schilling had yet to make her contribution in Oct?
However the same is true for the 109, the 109 in March/April 109 was often not the 109 in use in October.
For the Japanese the Ki 43 was a prototype or two in 1940, not even the combat test the A6M2 got. The A6M2 also had a structual problem with the wing althtugh they didn't find that out until after Oct 1940 but did fix it well before Peral Harbor.
P-40s in the time frame had no self sealing tanks, no armor and the engines were going back to the factory to be reworked because they would not last until the desired overhaul times.
Others have posted here that the RR Merlin could be flown inverted, because that is only minus 1 G with respect to the carburettor, the problem was with much higher negative G as experienced when rapidly entering a dive. From memory the engine suffered very short fuel starvation then a "flooded" engine (or maybe the other way around)
The big surprise out of that to me was that stressed skin wings were so much lighter.
Wild_Bill_Kelso
Senior Master Sergeant
- 3,231
- Mar 18, 2022
Paint (dope?) is heavy
No, to get the required strength for combat loads the canvas/ dope wings needed much more metal inside. The metal skin allowed much weight to be taken out.
FLYBOYJ
"THE GREAT GAZOO"
Not really but it can develop considerable weight depending on the type of fabric, amount of seams and stitching, the method of attachment and the amount of dope and paint layers applied.
Canvas IS NOT used on fabric aircraft, it's way too heavy!!! - mercerized cotton was the common covering and later Ceconite (a nylon-based fabric) was used.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
If I remember right, Dacron, which is a synthetic material, was used as a replacement for organic covering starting around WWII (early-mid 1940's).
FLYBOYJ
"THE GREAT GAZOO"
Dacron and Ceconite are the same and yes, they replaced organic coverings.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
For what it's worth, Dacron (Nylon) was developed to replace Japanese Silk.
While that's great and all for the aircraft industry, I'm thinking of the benefits of a pair of Nylons on a girl
Hi
Drawings of the Hurricane fabric covered and metal covered wings below for comparison:
Mike
Jagdflieger
Senior Airman
- 580
- Mar 23, 2022
Great info thanks - any figures in regards to weight differences (only concerning the wings) available?
Regards
Jagdflieger
Hi
I have yet to find the weight differences of the wings. Weights in general tend to differ from publication to publication, as a compromise here is the specification table from 'The Hawker Hurricane I' Profile Publication No. 111, includes 'early' and 'late' model Mk. I:
Mike
I have seen the weight difference on the "net" which was the reason for my comment, I cant remember where I read it or what the weight difference was but it was much more than I thought possible, however understandable when you see the drawings.
FLYBOYJ
"THE GREAT GAZOO"
I believe it was and IIRC was considered the best fabric to use before the synthetics came into play
Howard Gibson
Senior Airman
I thought the British used something called "Irish linen".For what it's worth, Dacron (Nylon) was developed to replace Japanese Silk.
While that's great and all for the aircraft industry, I'm thinking of the benefits of a pair of Nylons on a girl
One of the horrors of war is that materials that look nifty of women get reserved for something military.
