Engine technology free-for-all

[J.A.W.]

Well that was the trials result as reported.. ..maybe they used squadron aircraft rather than R-R factory specials?
& Spit XII was never any kind of real match for the Typhoon, hence ~100 built vs 3,300..

Service pilots also ran impromptu speed contests,
& sure W, you are correct - that brute Sabre power could see off any single-speed supercharged RAF Spit..

Beamont, as Hawker test-pilot was charged with full-out flying to help determine the 'tail gone' issue..
..including Mach crit dives & max G pull- outs.. ..according to his memoirs..

& wee Brown went a bit quicker in the Tempest didn't he - Mach 0.87, wasn't it?

Not that the Spit test value margin - was of any practicable use in combat anyhow..

& gravity is pretty weak, diving is a deliberate, precise action, & it is power & aero that counts..

Spitfires were mostly modestly powered & fairly draggy, the P-51 was much slicker, they could even
out-dive the more powerful Griffon Spits, even if those weighed more than Merlin Spits..

[wuzak]

Well that was the trials result as reported.. ..maybe they used squadron aircraft rather than R-R factory specials?
& Spit XII was never any kind of real match for the Typhoon, hence ~100 built vs 3,300..

They stopped building XIIs and started building XIVs.

The XII was within a few mph of the Typhoon at low altitudes. It rolled better (most were fitted with clipped wing tips), climbed better and turned better.

The Typhoon largely went over to ground attack duties, while the XII remained on fighter duties until replaced by the XIV.

[Tommy Cookers]

iirc the XII was a conversion of the (abandoned) III (this had more clipping than any other production Spit)
so the XII was a limited development to respond to the 190 low altitude capability
but naughty RR or VS used the XII to represent the capability of the 2 stage Griffon for low altitude speed

and surely the turbo gave the 47 and 38 an all-altitudes capability, being faster at altitude than anything without 3 speeds
rather wasted by the 38 airframe

btw a proper aero person told me that a Spit went in at Dunkirk with a sonic boom
and in the book Heelicopter the author (Sikorsky's mechanical designer) reports seeing a P-47 do the same
(and he explains how cyclic pitch variation is not needed but happened anyway)

[J.A.W.]

Fairly few Griffon Spitfires were built/saw action, & all Spits lacked the ability of the big Hawker fighters
to deliver heavy ordnance loads or maintain such high speeds in doing so.. ..Typhoon performance was
steadily improving with aero-clean ups, better props & higher boost level Sabres - as available..

The USAAF turbo-boosted P-38 & P-47 were, in the ETO relegated (by the performance of the Merlin Mustang)
to low level roles - where they were not at their performance best..

Neither P-38 or P-47 were fast enough to catch V1 cruise missiles - which jetted in - at low level.
Nor was either of those 2 able to make much impression in post war air racing, inc' Reno..

The R-R powered machines were, when highly boosted, & the Sabre-Tempest was even better, at lower boost levels.

The ability of the Sabre to tolerate high power settings for long periods was also useful in ''Rat Catching"
- Me 262 pursuits, with a number of instances where the new-fangled turbine mills wilted 1st under
the strain of the chase, much as the BMW radials powering FW 190 JABOs did when under hot pursuit
by Sabre-powered Typhoons racing back from Blighty, earlier in the war..

[wuzak]

Fairly few Griffon Spitfires were built/saw action, & all Spits lacked the ability of the big Hawker fighters
to deliver heavy ordnance loads or maintain such high speeds in doing so.. ..Typhoon performance was
steadily improving with aero-clean ups, better props & higher boost level Sabres - as available..

It is interesting that while the Typhoon was intended to replace the Spitfire it was completely unable to.

And that the big plus for the Typhoon/Tempest was their ability to carry bombs and rockets - which was not their intended role. They were supposed to be inetreceptors, but instead operated as fighter-bombers.

No, there weren't that many Griffon Spitfires built.Mainly because of the concentration on Merlin development and production of the IX/XVI instead of the VIII and XIV.

[J.A.W.]

Yes, there really were too many Merlins available & while not ideal as fighter-bombers..
.. most 2nd TAF Spits ended up doing that duty.. .. while carrying 'bout 1/2 the payload of the Typhoon..

Centaurus, Griffon, & Sabre production was very limited by comparison ( ~10% all told), even if those mills
offered superior performance in fighters that could accommodate them.

Typhoons did have the speed, endurance & firepower to do low-level JABO interception & offensive strike roles
..better than Spits however.. One Kiwi Spit ace (E.D Mackie) reckoned the Hawkers were "much more warlike..."

.. & the top Typhoon ace Johnny Baldwin - even successfully intercepted a Bf 109 when it was flying as top cover
( @ over 20,000ft) - escort to the FW 190 JABO mass daylight attack on London in Jan `43..

[J.A.W.]

This link below has a good write-up & pix of the Hawker Fury..

..which has - over the years - been flown with quite a few different mills..
(All 3 final big Brit production piston aero-engines originally, & latterly fitted with U.S. types too)

http://www.oldmachinepress.wordpress.co ... e-powered/

[trinidefender]

J.A.W. It seems you have a love affair with the typhoon. Let me also remind you that the spit climbed better. It's engine was generally more reliable (the sabre turned out to be a fairly reliable engine by wars end but had many teething problems initially), the sabre took more hours to work on with twice the number of cylinders and a major factor is at anything above abut 15,000 ft the spitfires speed margin grew. Basically for the purpose of intercepting bombers, the spit was perfect. It climbed fast, it was fast at high altitude and later on in the war with the hispano cannons added in it was a good gun platform.

The typhoon, while undeniably a very fast and nice aircraft was actually more suited to the roles it performed. Low level, chasing fighter/bomber fw190's that zipped along tree lines to bomb specific targets, troop support, bombing and rockets, generally more low level operation.

Two different aircraft suited to two very different roles.

[J.A.W.]

Steady on T.. ."love affair" is a tad personal..
..& certainly the Napier Sabre deserves the much of the credit.. being the sole world-wide example of..
.. the really high performance ( 2500+hp rating) liquid-cooled inline piston aero-engine to see service..

It is perhaps telling that Typhoon units were deemed so valuable in 1944 - that after the initial couple
of Typhoon squadrons transitioned to the new Tempest, from then on - Spitfire equipped squadrons were
directed to give up their machines in favour of flying the new Hawkers in post-invasion combat roles..
The RAF 2nd TAF being the primary British air-power contribution, & in medium/low altitude employment.
As the official trials show, the Sabre Tempest was the most potent Allied fighter available for this duty.

As in F1, the pilots were not concerned with how many cylinders or the price thereof in monetary
or ground-crew fettling terms, but just how hard they could successfully hammer them, & the opposition..

& It is truly a disgrace that the Brits scrapped every Sabre powered Hawker they had.
The rare survivors in museums today being latterly re-assembled from scrapped parts,
- or lucky enough to be overseas - when all the British planes were condemned..

[autogyro]

I think it is fair to say that the Typhoon Tempest and Fury were later designs than the Spitfire and were in the earlier stages of service development.
The later Spitfires were over engined, although the Crecy engined version would have been interesting to compare.

A good comparison is the P51 Mustang.
The early Allison engined versions were no good at altitude but it could be argued that the Allison could have been developed if the Merlin had not been used on the later models.

The problem is that the Fury and later Spitfire and other designs were overtaken by the jets, so most comparisons are educated guess work.

[wuzak]

There were different Spits for different roles. And different engines.

The Spitfire LF.IX wasn't as fast down low as the Typhoon. Actually wasn't as fast as later model Typhoons (best speeds), full stop. But they did climb and turn better, and were faster at altitude.

The XII was powered by a single stage Griffon and was fast down low. As fast as a contemporary Typhoon, but not the later ones with cleaned up details and more power. The XII could outclimb, out-roll and out-turn the Typhoon.

The XIV with the two stage Griffon was faster than the Typhoon at all altitudes, climbed better, turned better and rolled better.

The Tempest was more of a contemporary to the XIV, but was still somewhat later.

[J.A.W.]

The 1935-45 primacy era of the monoplane-aircraft piston engine was remarkable for its advances..

It seems that only now are the fundamental efficiency/power density/forced induction/compound-drives envisaged
for piston mills, - but cut off around that time, by the airspeed advantages of turbines - being utilized in motorsport
& yet - still somewhat tame in application - due to the current super-restrictive 'rules' that 'ban' so much..

[Tommy Cookers]

in F1 the (non-Mercedes) engine experts are presumably rushing right now to make their engines more Mercedes-like

in the 1940-41 winter experts similarly rushed to make the Spitfire more 109-like, ie the Spitfire Mk III, a blind alley
drastically cutting the wing back and fitting the bulkier and heavier 2 speed 20 series engine (another blind alley as Hooker showed)
aerodynamically degrading the altitude performance and simultaneously upgrading it by improving the boost at altitude
while elsewhere other experts made the 109E into the Spitfire-like 109F
extending and rounding-off the wing and nose
raising the power with racy cams and induction system preferred over boost improvement
experts designed the Typhoon, redesigned it into the Tempest, and redesigned that into the 'cut and shut' Fury
in panic for performance shortening the fuselage and wing and so degrading the stability and control (to Spit levels ?)
elsewhere the 210 was rescued from designed-in stability/control problems by going the opposite way (the 410), as did others

experts don't get their jobs without knowing which way the policy wind is blowing .... experts or fashionistas ?

eg the USN had fashionably slim 950 hp Twin Wasp Juniors at war when 1200 hp Twin Wasps could and should have been there
the whole 30s slim nose/slim nacelle fashion was based on faulty tunnel work that ignored the effect of prop action on flow
the 190 showed this (that the fuselage didn't need to be a teardrop/barrel shape)

also other countries example suggests that the UK and USA should have had bigger (and earlier) V12s
clearly WW2 policy was to choose aircraft types/roles related to WW1 'small engine - fighter/big engine - bomber' concept
but force onto this the WW2 'one engine/one engine size fits all' policy

btw the recent Sea Fury accident at Culdrose seems to have reminded some that the Centaurus was not notably reliable
and that the Hercules was de-rated in service (Varsities etc)
btw Lallement or Closterman had a Sabre with the MW/ADI boost - he only used it (the boost) once - so why did they bother ?

the real reason for a radial is that a valve or ring unsticking job on an individual below-par cylinder is easy (unless a sleeve valve)

[J.A.W.]

The Spitfire & Bf 109 both proved so good & amenable to development..
..that they outlasted not only contemporaries but also - proposed successors..
Indeed - they were overdeveloped, by fitment of more & more power - beyond the point of best overall performance..

@ T-C your views re: the Hawker Fury are a bit off, yes - it was a modernised/truncated Tempest,
but its flight characteristics did prove suitable for the fraught naval aircraft carrier ops role..
..something the rival 'laminar-flow' Spiteful/Sea Fang (Spitfire successor) could not match..

The Centaurus, has been shown to be intolerant of mis-handling, but when properly operated,
Sea Fury pilots have had the confidence to make long flights - even in recent times ,
..such as across the Tasman sea..
& you saw the time-distance flight record made by Neville Duke from London to Rome,
which beat the time set by a Vampire turbo-jet..

[olefud]

This may afford a bit more insight into the various country's and engines tradeoffs and oversights;

http://books.google.com/books?id=lo9TAA ... ve&f=false