1930: RAF buys DH.77 and Vickers Jockey?

[tomo pauk]

As it says on the tin - instead of biplanes, RAF moves on monoplane fighters. For the sake of discussion, DH replaces the Naiper Rapier engine with RR Kestrel on second prototype of the DH.77 (that historically never flew), that carries on the series produced examples.
What kind of capability increase we might see vs. the biplane-outfitted RAF fighter force of 1930s, what might be the plausible improvements for the monoplanes in question, what lessons other people might draw from this? Licence for other coutries; foreign users? Influence on RAF thinking/doctrine/startegy/requirements in 1930s?

 

[Shortround6]

Bring back the biplanes QUICK!!!!



Speed with military equipment was 185mph?
Hawker Fury with Kestrel could do over 200mph.
A crappy, high drag monoplane doesn't have many advantages over a cleaner biplane.
Trying to take a light weight fighter and stick a big engine in it is also going to lead to problems.
A 163 sq ft wing is fine when you weigh 2300lbs, add 4-500lbs of powerplant weight and the wing loading and stall speed go up (this plane was pre flap and early flaps were not lift devices but drag devices.

 

[tomo pauk]

Bring back the biplanes QUICK!!!!



Speed with military equipment was 185mph?
Hawker Fury with Kestrel could do over 200mph.

It could, with triple the power at 13000 ft. Rapier I was a worse altitude engine than the non-supercharged Fiat from the CR.30.

A crappy, high drag monoplane doesn't have many advantages over a cleaner biplane.
Trying to take a light weight fighter and stick a big engine in it is also going to lead to problems.
A 163 sq ft wing is fine when you weigh 2300lbs, add 4-500lbs of powerplant weight and the wing loading and stall speed go up (this plane was pre flap and early flaps were not lift devices but drag devices.

Kestrel was not a big engine, Fury biplane was not a miracle of streamlining.
I-16 went loaded between 3000 and 4000 lbs in 1930s, P-26A was at 3300 lbs.

 

[Shortround6]

The P-26 had problems with high landing speed (at least for it's time) and the later ones got flaps at the factory and the early ones were modified.
The Gloster Gladiator was the first RAF fighter (if not the first RAF airplane?) to get landing flaps.
Using a high wing loading (and in the late 20s anything over 20lbs/sq ft might be considered high) was well out of the ordinary.

Using the braced monoplane (either struts or wires) doesn't bring all of the advantages of the cantilever monoplane. You have the drag of the braces, and many such planes used the landing gear as part of the bracing system so trying to build a retracting landing gear braced monoplane is really difficult.
It took a while for the idea that a thick wing (cantilever) could have about the same drag as a thin wing with braces to sink into designers minds.

I would also note that the Kestrel engine, small as it seems compared to WW II engines was a large and heavy engine in the 1920s and early 30s.
The Curtiss D-12 1145cu in and 435hp weighed 680lbs
The Curtiss Conqueror 1570cu in and 600 hp weighed 845lbs with reduction gear.

All of these liquid cooled engines were using water as the coolant and needed large and heavy radiators. Glycol cooling with it's higher temperatures and resulting smaller amount of coolant and radiators was just around the corner. Please remember that the PV 12 engine was designed for evaporative cooling and not glycol although it was soon changed.

heavy engines and small wings gets us back to wing sections (high lift/high drag or??) and lift devices that were in their infancy.

A lot of things had to come together to get the monoplane fighters of the mid 30s.

 

[tomo pauk]

The P-26 had problems with high landing speed (at least for it's time) and the later ones got flaps at the factory and the early ones were modified.
The Gloster Gladiator was the first RAF fighter (if not the first RAF airplane?) to get landing flaps.
Using a high wing loading (and in the late 20s anything over 20lbs/sq ft might be considered high) was well out of the ordinary.

Using the braced monoplane (either struts or wires) doesn't bring all of the advantages of the cantilever monoplane. You have the drag of the braces, and many such planes used the landing gear as part of the bracing system so trying to build a retracting landing gear braced monoplane is really difficult.
It took a while for the idea that a thick wing (cantilever) could have about the same drag as a thin wing with braces to sink into designers minds.

Earlier the designers tackle the monoplane fighters' design, earlier the issues can be adressed, both in design phase and in service.

I would also note that the Kestrel engine, small as it seems compared to WW II engines was a large and heavy engine in the 1920s and early 30s.
The Curtiss D-12 1145cu in and 435hp weighed 680lbs
The Curtiss Conqueror 1570cu in and 600 hp weighed 845lbs with reduction gear.

R-1830-1 and -3: 1180 lbs
R-1820E: 850-950 lbs; R-1820F (from 1932): 1000-1100
Dagger I: 1300 lbs?
Fiat A.30: 1060 lbs dry
BMW VI: 1120 lbs dry (without reduction gear)
Lion: 900-1000 lbs
Buzzard: 1540 lbs

Either of these engines, bar A.30 and Dagger, were also much bigger than Kestrel, that weighted 900 lbs dry in 1st iterations,

All of these liquid cooled engines were using water as the coolant and needed large and heavy radiators. Glycol cooling with it's higher temperatures and resulting smaller amount of coolant and radiators was just around the corner. Please remember that the PV 12 engine was designed for evaporative cooling and not glycol although it was soon changed.
heavy engines and small wings gets us back to wing sections (high lift/high drag or??) and lift devices that were in their infancy.
A lot of things had to come together to get the monoplane fighters of the mid 30s.

Radiator on the Fiat CR.32 weighted 40 kg.

 

[Shortround6]

Point is sticking any of those engines on the DH 77 would have been a rather difficult task.

BTW the engine used on the P-26 weighed a whopping 715lbs.

Hispano Suiza 12X engine about 815lbs with supercharger.
Hispano Suiza 12Y engine about 1034lbs with supercharger.

A lot of progress was made in the years between 1929 (first flight of the DH 77) and 1934-35 (design work on many of the monoplanes of WW II) and no one feature could really show a dominant effect for several years. You might have a plane with a low drag wing set up (cantilever monoplane)

That is handicapped by a poor engine installation (not even a Townsend ring) or other not so advanced feature. This made it hard to pick out the really useful features,
You had influential people in England convinced that Biplanes outclimbed monoplanes due to greater lift (in theory, there were very few experiments to test it) and it took awhile for the theory (provable) that the lower drag monoplane actually climbed faster due to a higher surplus of power.

Compound this with the fact that all the smaller airforces what proven machinery, either engines or airframes and don't want to be funding experiments for larger wealthier countries.

The two lightweight British monoplanes of 1929-30 were pretty much dead ends due to size and inability to demonstrate significant performance advantages (in part due to other problems than the wing)

 

[tomo pauk]

Point is sticking any of those engines on the DH 77 would have been a rather difficult task.

BTW the engine used on the P-26 weighed a whopping 715lbs.

Hispano Suiza 12X engine about 815lbs with supercharger.
Hispano Suiza 12Y engine about 1034lbs with supercharger.

A lot of progress was made in the years between 1929 (first flight of the DH 77) and 1934-35 (design work on many of the monoplanes of WW II) and no one feature could really show a dominant effect for several years. You might have a plane with a low drag wing set up (cantilever monoplane)

That is handicapped by a poor engine installation (not even a Townsend ring) or other not so advanced feature. This made it hard to pick out the really useful features,

Good. Then we'll have the Jockey with Townsend ring, then with NACA cowling + Mercury engine. Enclosed cockpit by mid-1930s, as well as retractable U/C.

You had influential people in England convinced that Biplanes outclimbed monoplanes due to greater lift (in theory, there were very few experiments to test it) and it took awhile for the theory (provable) that the lower drag monoplane actually climbed faster due to a higher surplus of power.

IIRC the monoplanes were called 'American novelty' during 1st half of 1930s by British aero-mided (airminded?) press.

Compound this with the fact that all the smaller airforces what proven machinery, either engines or airframes and don't want to be funding experiments for larger wealthier countries.

The two lightweight British monoplanes of 1929-30 were pretty much dead ends due to size and inability to demonstrate significant performance advantages (in part due to other problems than the wing)

I can't recall suggesting the small countries pay for wealthy coutries' experiments.
Nothing prevents Hawker or Supermarine to offer better stuff in mid-1930s.