Last & Best of the Piston Engine Fighter Aircraft.

Post anything that doesn't belong in any other forum, including gaming and topics unrelated to motorsport. Site specific discussions should go in the site feedback forum.
Tommy Cookers
Tommy Cookers
547
Joined: Fri Feb 17, 2012 3:55 pm

Re: Last & Best of the Piston Engine Fighter Aircraft.

Post

another plane that was out of control before it left the ground (Spitfire-mockers might note) was the Tornado/Typhoon
(as I've said before a wide-track undercarriage isn't a magic problem-solver)

the Tornado prototype (though designed to do so) couldn't be kept straight during take-off runs (at Langley)
so for 6 months its pilot Phillip Lucas used his own curved path that only met the runway at the point of take-off
(with the Typhoon prototype Mr Lucas avoided this due to immediate in-flight structural failures)

similarly the (production) Typhoon I was in AFDU Report 37 (30.10.1941) said to be ....
incapable of takeoff in a starboard crosswind ('such operations should be avoided')
and the Tempest II required according to CFE Report 30 (5.7.1945) ......
to contain the swing 'the throttle must be opened slowly'
the swing is also mentioned as a factor in night landings
btw too many Mosquito crew died in this situation
(someone wrote that one night group used their own low rpm to avoid this - less 'gyroscopic' torque of course)
(on TV an ex-Mossie Canadian said in prime adspeak that it was - 'unforgiving of those who under-controlled it')

an outstanding read .....
https://vintageaviationecho.com/bf109e/
I flew with a Buchon owner
afaik the 109 'handed' fin that Wiki worship says Buchons kept exactly (or the rudder) was actually realigned to compensate


the Typhoon's conspicuously low stalling speed was presumably because max Cl rises with wing % thickness ....
and the Tempest's benign near-stall behaviour screams out that the aerofoil wasn't really 'laminar'
(and I see that the Wiki gang talks nonsense about Merlin negative g cuts - a restrictor cures rich cuts)

the Tornado (Vulture) engine seems to have been debugged eventually - and 'Merlinised' bore' 5.4" x 5.5" work started
the V was lighter than the Sabre ? - one crankshaft being lighter than two

btw a non-work acquaintance told me the BAe Tornado ADV radar installation mock-up BAe gave to GEC was wrong
ie this was the reason the radar as designed and made by GEC wouldn't fit in the BAe Tornado ADV plane

J.A.W.
J.A.W.
95
Joined: Mon Sep 01, 2014 4:10 am
Location: Altair IV.

Re: Last & Best of the Piston Engine Fighter Aircraft.

Post

Yeah, T-C, quite a few lurid assumptions in your most recent post...

A check of operational losses (combat & non-combat) shows that even the
heavily laden Bomber Command Mosquitos had an admirable sortie/loss %,
even compared to the 4-engined 'heavies', let alone other twins...

Same goes for the Typhoon, which in that 1941 AFDU test not only 'burst the Spit=best bubble',
but once fitted with a 4-blade prop, & Tempest tail-plane, showed it was a much more effective
close-support aircraft for the invasion of 'Festung Europa' compared to the vast numbers of Spits
on hand, (& the USAAF turbo-charged fighters) roped into the same job..

Again, the thick-winged Typhoon gave good low-speed lift, but like the Hurricane, was risky
to ditch on the sea, due to the 'stop-dead' characteristics of that fat-profile wing, something
remediated by the Tempest/Sea Fury, which 'skipped' across, just as scale tank-tests predicted.

I'd also suggest that the semi-elliptical planform also offers a characteristically forgiving stall
profile, 'laminar flow' or no, due to the propensity of the shape in giving even stall, span-wise,
with plenty of forewarning. Of course, the Hawker machines were stoutly constructed also,
& allowed a fair degree of 'liberty taking' in flight regime extremis, without falling apart in mid-air..
We are standing on the shoulders of Giants. So wash your feet.

J.A.W.
J.A.W.
95
Joined: Mon Sep 01, 2014 4:10 am
Location: Altair IV.

Re: Last & Best of the Piston Engine Fighter Aircraft.

Post

Here is a link to that 1941 AFDU Typhoon versus Spitfire Tactical Trial:

http://www.wwiiaircraftperformance.org/ ... Trials.pdf

It ironically enough, forewarned the effect of the - soon to arrive Focke Wulf FW190,
(while both the FW 190 & Typhoon were 'rushed' into service, with problems causing
consternation to combat pilots accordingly, the Germans at least, 'got cracking' on
both fixing their issues & mass producing the BMW engine & aircraft in useful numbers)
which came as a shock - to the complacent 'Spitfire Mafia'.

AFAIR, Hawker test pilot Mr Lucas ('Are you free, Mr Lucas?') later admitted the structural
(but not fatal) damage suffered by the (then sole!) prototype Typhoon was his doing,
by 'pushing the envelope' as the American test pilots would put it, & performing evolutions
exceeding the intended test-program profile.

The ill-fated R/R Vulture did behave itself when powering the Typhoon's near-sister Tornado,
but not doing bomber-work (unlike the BMW) & did any X-crank see satisfactory service?

Certainly R/R gave up on it, & tried to have 'a bob each way' by building an oversized,
overweight (& yet unreliable) Sabre-clone which was 'too much, too late', & a scaled-up
'old hand' V12 in the Griffon, which while of similar cubic capacity (~36 litre) to the Sabre,
was unable to match its performance - so, ironically the Sea Fury was accepted for naval
service with the big Bristol Centaurus - although the Griffon was already shipborne in
Seafire & Firefly, thus adding another logistics complication, (& that's just so British, too).
We are standing on the shoulders of Giants. So wash your feet.

Tommy Cookers
Tommy Cookers
547
Joined: Fri Feb 17, 2012 3:55 pm

Re: Last & Best of the Piston Engine Fighter Aircraft.

Post

the H16 BRM was designed in emulation of the Sabre - but WW2 had no engine rules ....
the only engine 'size' (limiting factors) were the physical dimensions and the weight
the Sabre was 'big' - and the Centaurus was odd - having Hercules bore but a much longer (Orion-size) stroke
was that to use Orion-design parts ? (after the Orion went out of the door in 1941 with Mr Fedden)


all planes have less thrust during the take-off roll than at the point of take-off and in initial climb
because the prop's conversion of mechanical power to thrust increases with airspeed
rushing towards WOT gives more rpm and much more boost - this then causes more autothrottling to hold down boost
... two reasons why it's good not to rush to WOT - even in a non-Spitfire

the later introduction of auto ie single-lever control of power and pitch seemed to enforce this (discreetly)
ie in later a/c such as Tempests (and I presume with later Mosquitos)
single-lever giving lower rpm through the take-off roll (compared to old separate command of rpm by pitch control lever)

also the later props mostly were less efficient converters at runway speeds (especially the contra-rotators)
(because typically smaller diameter with the same power or the same diameter with increased power)

notice iirc the fixed pitch Spitfire/Hurricane prop weighed 84 lb and the early 3 blade VP comparison weighed 342 lb
so it seems the plane (for the comparison tests) artificially had 150 lb of ballast when FP (ok 40 lb ballast when VP)
and the 'last gasp' Italian Schneider Trophy 24 cylinder - it's contra-prop gave the design smaller so shorter floats
but their shorter length was slower to unstick - takeoff runs were 2 miles
maybe the earlier designers knew what they were doing


that Mr Shenstone seemed to know what he was doing .....

in effect NACA invited design of airfoils via a unified system of 'formulae' derived from outstanding airfoils worldwide
NACA 22s didn't exist as proven designs unless/until someone outside NACA made and tested them (at realistic Re nos)
ie NACA made and tested and reported on the 00 and 23 and 46 families and many others - but never 22s
eg NACA Report 460 1933 and NACA technical Note 487
460 shows that 2312 (12% thick) is probably the best 23 aerodynamically (ignoring structural properties of course)
487 shows that the 'old' Clark Y was better in lift coefficient than the 22s

Shenstone was talking to Bellanca - and the Spitfire acquired fillets like the (long-distance racer) Bellanca 28-70
that used a (Bellanca) 'type M high lift' airfoil c.12% thick - its performance was clearly outstanding (record breaking)
the 28 having a rather forward mainspar and external bracing - the 'M' was quite similar to the NACA 22 'formula'
Shenstone presumably chose the 2212 (rather than 2312) because of the Spitfire's 'single' spar web being rather far forward
btw/iirc using the modern convention for the point of 'tip thickness' some determine the Spit tip aerofoil as 2208.5
the 2212 seems to have been the best match to the ongoing Spitfire structure established around steam cooling

elliptical wings give less induced drag so mainly help at high altitudes not low (Typhoon/Tempest) altitudes
Last edited by Tommy Cookers on Thu Feb 25, 2021 1:18 am, edited 2 times in total.

J.A.W.
J.A.W.
95
Joined: Mon Sep 01, 2014 4:10 am
Location: Altair IV.

Re: Last & Best of the Piston Engine Fighter Aircraft.

Post

The Macchi 'twin twelve' seaplane which was indeed fast enough to take
(& hold, to this day) the seaplane speed record was too late to stop
Supermarine taking the Schneider Trophy for Britain in perpetuity,
but of course had each V12 powering a coarse/fixed-pitch wooden prop,
so every take-off was bound to be to be a 'judicious' event, counter
rotating props, or no.

The extra blade added by using the Tempest prop on the Typhoon,
shortened take-off distance (& reduced the fatiguing buzz-vibration),
- something the late-production Corsairs emulated - while that inverted
'gull-wing' was intended to provide both prop-disc clearance & also a
root attachment which did not require the Spitfire's elaborate fillets.
We are standing on the shoulders of Giants. So wash your feet.