Advantages of sleeve valves for H-24 engines?

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Incorrect assumption

Ok, good, so then you agree that if the Tempest V hadn't been available, all of the 800 V-1's the Tempests shot down wouldn't have rained down over London.

Maybe the alternative approaches they would have devised would have shot down more than the 800 shot down by the Tempests, maybe less.

The Mustang's 4 x .50" gun fit was puny* compared to the
4 x 20mm

Now we seem to be rapidly shifting the goalposts, but anyway, I fully agree that 4x20mm is far superior to 4x.50, but OTOH for shooting down a non-maneuvering target that has a very limited capability to absorb damage even compared to a single-engine fighter, I'm not sure it's a particularly big issue.


Clearly the Meteor in mid 1944 was for all practical purposes a prototype. One reason I read somewhere for the meager success against the V-1's was that they had problems with the cannons jamming. Of course a serious problem for a combat aircraft, but nothing per se to do with the powerplant and no reason to believe it couldn't be fixed, as many other aircraft were very successfully using cannons by that time.

My point was that if all the effort they spent on the sleeve valves had been directed at jets instead, the Meteor might have been a much more formidable aircraft already by mid-1944. And of course, if the Tempest with the Sabre wouldn't exist, chances are the Typhoon wouldn't exist either, and Gloster would perhaps had more capacity for Meteor.
 
Its perfectly evident z42 that you make too many assumptions, & fail to grasp the facts. Shooting down tiny missiles flying fast, with nearly
a ton of warhead aboard wasn't like shooting clay-pigeons with a shotgun...
Do read up on the difficulties involved, if you really are interested. As for an effective turbo-jet fighter, they were trying, maybe if they'd
cut Merlin production by 1/2 - so only useful airframes got them, the funds could've been spent by R/R on turbines...

The Sabre-Tempest was the RAF's top-performance low-medium level fighter, & the V1 victory results speak for themselves.
I see you are familiar with the wwiiaircraftperformance site, by all means check the late 1943 tactical trials outcome which states this,
& note that was with a low-boost engine compared to later production units.
 
What, Flight Magazine ?

It was read by the Germans during the war, and was heavily censored and obviously very heavily edited to make sure it was always good propaganda.
'Flight & the Aircraft Engineer' also re-published German journal articles, I was amazed to see a translated piece which not only showed how
impressive the Germans found the Sabre, but also a 'laminar-flow' wing profile which was a virtual match for the NPL/Hawker 'high-speed'
profile which was fitted to Tempest/Fury. What was even more amazing, was this was in 1942, & the Typhoon was only just operational.

Can you dispute any of the data presented in the linked article? Mocking isn't a substitute for critical analysis...
 
It says absolutely nothing inside which is even relevant to any of your points - and the mocking was well deserved - which was directed at your thinking that a propaganda magazine is a primary archive source.
 
It says absolutely nothing inside which is even relevant to any of your points - and the mocking was well deserved - which was directed at your thinking that a propaganda magazine is a primary archive source.
So... you didn't read it, evidently... The technical data is accurate, as any German Engineer examining a Sabre himself with that journal in
front of him contemporaneously could perfectly well fact-check.
 
So... you didn't read it, evidently... The technical data is accurate, as any German Engineer examining a Sabre himself with that journal in
front of him contemporaneously could perfectly well fact-check.
What on earth are you talking about ?

Literally the only thing it says about performance is that it developed 2200hp, the rest is a descritpion of the design features.

You`ve spent half this arguing that it ended up 3500hp
 
What was failing? The de Havilland propeller oil-seal? Or was it throwing a blade, just as later, in Europe @ +13lb boost, pre-Rotol props.
Cracked cylinder heads, cracked cylinder blocks and broken engine propellor shafts.

Even the Spitfire IX LF was faster at sea level with both on 150 grade.

They expected no possibility of getting the Sabre beyond +11lbs even on 150 grade, by which point the Spitfire IX
was at +25lbs.

 
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the effort they spent on the sleeve valves

We must not forget the extraordinary reputation enjoyed by Harry Ricardo in the 1930s. However, this guru came to the conclusion that sleeve valves were a credible alternative to poppet valves, or even superior to them - see the first editions (1923, 1931, 1941) of his famous "High-speed internal-combustion engine" - number 1 in Raymond's references.

And don't forget either that in the time when the Sabre was failing, Bristol had already enjoyed real successes with its sleeve-valves engines.

Under these conditions, we can understand that for some ingineers and decision-makers the development of the Sabre was not understood as a dead end and a waste of time.
 
This is all true, but it is also true that plenty of even the Bristol engineers at the time had deep misgivings.

(This is Feddens own letter)

 
What on earth are you talking about ?

Literally the only thing it says about performance is that it developed 2200hp, the rest is a descritpion of the design features.

You`ve spent half this arguing that it ended up 3500hp
My previous post (#111) shows a quote from Ricardo's book that the Sabre achieved a sustained output of 3600 hp.
 
My previous post (#111) shows a quote from Ricardo's book that the Sabre achieved a sustained output of 3600 hp.
Well nobody appears to have told Napier that, because there are no test results for that, only a projected output for the mooted E.122 version, which was never built.

"sustained output" can mean anything, could be 2 minuites. Merlin`s could do over 2700hp for short periods of "sustained" load on special tests before the war even ended.
A "this once did this number on a dyno" is a universe from "type tested".

Clearly that wasnt type tested, or it would be in the ministry records (which it isnt).

All the experimental evidence (on charts which actually say "from experimental tests") all say that 3050hp was the highest ever recorded rating.

Even Napiers own post war tables have nothing above 3055 (going to about 1948).

 
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Ricardo was a highly respected member of the Royal Aeronautical Society for decades. I find it implausible that Ricardo made it up. He gained no benefit from publishing that performance number.
I guess it comes down to if you respect him or not. Having read a number of his books and papers, I am inclined to accept his information. Having read your book, I expect you to reject it.
 
Yes... But after leaving Bristol, Fedden worked on a car project, with a sleeve-valves engine !
Fedden also worked on a flat 6.

But it seems they were looking backwards. Making a better engine than the Gipsy series of engines in the post war was pretty low hanging fruit. The American flat 4s and flat 6s were going to take over the world market ( and had been being made right before WW II so they were not NEW.)
 
Another person who cant read ?

Its entirely possible that a brief sprint test was made where once, for a few minuites "a" sabre of some description achieved a high power level.

This is literally nothing to do with the wartime usage of it, or what was type tested, and among all engines one can find high power tests
which are of no relevance to the real use of the engine.

I`m afraid that sleeve-valve fan boys like you who dont "like" my book for revealing what a catastrophe they were using only primany source archive files, are
not my concern. Facts dont care about your feelings, or your rather dismally transparent insults about my book.

It is most amusing that you rate a book written from memory, many years after the facts, by someone who inspired people to use sleeve valves in the first
place is an un-biased source.

There is no evidence in the napier archive that such an engine was ever built or ever actually ran. Their review documents wax lyrical about the high power achieved in the VII of 3050hp, why do none of them mention this magical 3500hp figure ?
 

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