Advantages of sleeve valves for H-24 engines?

[J.A.W.]

I copy pasted this into Google Translate and it said:

"I am too embarrassed to admit I made a mistake"

Funny, you could attribute those words to yourself, too - recall when you claimed no Sabre was type-tested at over +10lb boost?
Yet the evidence arose to prove that assumption - while based on what you'd gleaned to that point - was incorrect.

 

[J.A.W.]

List them >

Here's one, (& hey, its right up your alley) - when Cosworth proposed an F1 sleeve valve mill, it was promptly kyboshed by the FIA!)

 

[J.A.W.]

that looks like something from a PC game i used to play !!

Yeah it does! Would that game be: 'Crimson Skies'?

 

[J.A.W.]

You stated that having read it you "knew" that I would make negative statements about sleeve valves, implying that the book is a result of my bias, instead of what the reality is, which is that the book is simply a large collection of faithfully reprinted letters from the time showing exactly what was said at the time.

Some people asked things like "you know if you had just paraphrased those letters instead of typing them all out at such length word-for-word you could have made the book 1/3 the size." The reason I didn't cut out the letters was to avoid things like this thread happening.

C'mon now, you def' hang your biases out here, & self-aware or not, that is inevitably going to present in selection/commentary by the author.

 

[J.A.W.]

I didn't avoid mentioning it. The rating of 3050 hp is what Ricardo wrote in his book, as I quoted in post 111. I have never claimed the max power rating was anything other than 3050 hp.
I saw no reason to bring up E122, as it was never run.

Or was it? A wee while ago, a member linked a site to aircraft crashes in the UK, & one I looked at - noted a flight out of Luton, being a test
flight of an experimental Napier-powered aircraft, & listed the engine as a 'Sabre VIII' - ok it could've been a typo, but maybe not?

 

[Simon Thomas]

That is interesting. It wouldn't be the first time something has been emphatically denied, and then a document turns up to show it is true.

There would have been far more Napier documentation prior to RR getting involved. Some may exist out there that isn't in the Napier Heritage Trust or IMechE.
The book "By Precision into Power" lists more Sabre series engines than has been listed on this thread.

Edit: added 'been' to the first line to make it read better.

 

[J.A.W.]

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.

View attachment 759698

Right, & these issues were encountered in an aircraft only recently introduced to service, & then pressed into vital defence duty.
Of course, the writer got it wrong about the likelihood of further boost increases, unless he meant real short term.

Check the site linked below, scroll down the combat reports to the end, and see the comment by Ron Dennis
(who'd run down an Me262 at max-boost "400mph IAS @ 0ft" for over 10min, to share the kill with his wing man)
about the sensitives of available propellors given the Sabres power (14ft prop - can you find a WWII fighter with a bigger one?)

https://www.wwiiaircraftperformance.org/tempest/tempest-V.html

 

[J.A.W.]

Please show me where I trashed your book.

Indeed, he's 'projected' - as very sensitive to any perceived criticism of his baby, ah, book - regardless of how corrective/reality-based it is.

 

[wuzak]

Here's one, (& hey, its right up your alley) - when Cosworth proposed an F1 sleeve valve mill, it was promptly kyboshed by the FIA!)

When was that?

 

[rochie]

Indeed, he's 'projected' - as very sensitive to any perceived criticism of his baby, ah, book - regardless of how corrective/reality-based it is.

J.A.W. i asked you to tone it down, you didn't listen !

to others, stop the personal jibes.

 

[Deleted member 68059]

C'mon now, you def' hang your biases out here, & self-aware or not, that is inevitably going to present in selection/commentary by the author.

Nope, I`ve simply read the relevant files and am reporting what they say, as evidenced by the trove of actual letters and data I`ve posted to support literally every point I`ve made.

 

[Deleted member 68059]

When was that?

We`ll perhaps find out more, I`ve just asked the former chief designer.

Mercedes made a mad barrell valve F1 engine head once. It was never raced, it was shown in Race Engine Technology magazine a few years ago.

I was told informally that the reason it was all put in a magazine was that it wasnt viable, athough the FIA would also certainly have banned it
these days on cost grounds. F1 is a really bad place for major engine innovation now, doing anything very different costs the budget necessary to start
a small war in the 3rd world somewhere. Ditching the turbocompound for 2026 was stupid, but necessary to drop entry costs enough to get new
competitors to sign up (aledgedly, - I think the real reason is just to slowly start making the engine more and more rubbish and gradually
replace it with more and more of an electrified powertrain until one day someone says - "hey might as well not have the engine?"
at which point it will turn into Formula-E, so much for Ross Brawn reforming the FIA ! )

 

[Engineman]

Agree. Off topic, the unpleasant criminal duo made F1 a political money machine.

Eng

 

[Bretoal2]

A QUESTION...

We have seen in this forum, about a year ago (more or less...) , a very unusual graph comparing the main great engines of WWII. It integrated, as I remember, power, RPM and BMEP.

The Sabre was credited by 3.900 hp and the drawing showed that this was obviously "out or range".

I'm unable to find back this drawing. Any idea ? Thanks !

 

[Deleted member 68059]

Here's one, (& hey, its right up your alley) - when Cosworth proposed an F1 sleeve valve mill, it was promptly kyboshed by the FIA!)

So my Cosworth contact says he never heard of any such engine, the thinking is that you have probably gotten very mixed up reading some forums,
and confused it with the rotary valve engine, which was he says actually done by Ilmor for Mercedes, and this is what was published in the magazine.

Its not a sleeve valve engine, and it was this which was banned by the FIA.

Incidentally you can find this exact valve layout in German aero engine publications from about 1938.

https://www.v-eight.com/multimedia/pdf/AutoTechBRV.pdf

 

[DerAdlerIstGelandet]

guys cut out the personal jibes, i'm getting bored of it !

Like clockwork…

 

[z42]

So my Cosworth contact says he never heard of any such engine

The wikipedia sleeve valve page has this to say:

Mike Hewland with his assistant John Logan, and also independently Keith Duckworth, experimented with a single-cylinder sleeve-valve test engine when looking at Cosworth DFV replacements. Hewland claimed to have obtained 72 hp (54 kW) from a 500 cc single-cylinder engine, with a specific fuel consumption of 177–205 g/HP/hr (0.39–0.45 lb/HP/hr), the engine being able to work on creosote, and with no specific lubrication supply for the sleeve.

However no references are given for this statement.

 

[DerAdlerIstGelandet]

rochie has asked each and every one of you to kindly tone it down with the snide comment and personal attacks, and yet he is being ignored by practically everyone. Like a kindergarten.

 

[Deleted member 68059]

The wikipedia sleeve valve page has this to say:



However no references are given for this statement.

Possibly, that was before the guy I know worked there. But in terms of the actual built engine which was banned by the FIA, its the one shown above ^

 

[Simon Thomas]

List them >

From "Short Stirling, The First of the RAF Heavy Bombers" written by Pino Lombardi 2015. Page 181 Paragraph 1. Trials were made with both the Hercules II and the Wright Cyclone (actually the GR-2600-A5B). The findings were the sleeve valve had the following advantages over the poppet valve.
(2) Performance
(3) Fuel Consumption
(4) Noise

This comparison is obviously the same aeroplane with the only change being the engines, which provides the only like-for-like real world comparison I have found.

I showed a comparison of the performance curves and bsfc in this thread:

Short Stirling Engines - Hercules XI & Wright GR2600A5B

Does anyone have a copy of the performance curve for the Wright GR2600A5B fitted to the Short Stirling? I am hoping to compare the performance curves of that and the Hercules XI. In the book "Short Stirling, The First of the RAF Heavy Bombers", Pino Lombardi writes However, Hercules engine...

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