16 replies to this topic

[Nev]

When I was younger (14 to 18) I used to fly gliders from a West German military base which hosted a squadron of Starfighters. In those days (incredibly) I could just walk right up to them and remember their fascinating static engine tests with me standing maybe 20 feet away. I remember running my fingers along the leading edges of the wings and almost drawing blood, the unusual smell of their fuel, the regular sonic booms and the sheer thrill of the ground vibrating.

 

Little did I know that 30 years later I would end up working for General Electric (who made their impressive J79 engines), in charge of the process control systems that made them. These things were the pinnacle of engineering in their day, with no compromise to sound levels or saving the planet. In those days it was all about saving ourselves from the Ruski menace and West German Starfighters were the closest primary response to any bomber threats. Their job was simple, scramble as fast as possible, gain altitude as fast as possible and shoot down as much as they could before they ran out of fuel or got shot down themselves.

 

Here's a J79 on full reheat, turn up the volume and feel your spine tingle:

 

Edited by Nev, 25 November 2017 - 10:36 AM.

[Madmitch]

Fantastic!!  My father spent WWII as Chief Draughtsman at Fairey Aviation, moving to High Duty Alloys right at the end of the war.  At HDA he was involved in the development of the early high temperature alloys, necessary for the transition from centrifugal flow gas turbines to axial flow gas turbines.  I still have two prototype turbine blades on my desk here, forged but still with their sprue around the edges.  We used to go to Farnborough every year on dad's Trade Pass, amazing time with fantastic low level displays OVER the spectators, the plane that really sticks in my memory though is the Fairey Delta flown by Peter Twiss which smashed the 1000mph barrier with a speed of 1132mph, no less!!  

[Nev]

Fantastic!!  My father spent WWII as Chief Draughtsman at Fairey Aviation, moving to High Duty Alloys right at the end of the war.  At HDA he was involved in the development of the early high temperature alloys, necessary for the transition from centrifugal flow gas turbines to axial flow gas turbines.  I still have two prototype turbine blades on my desk here, forged but still with their sprue around the edges.  We used to go to Farnborough every year on dad's Trade Pass, amazing time with fantastic low level displays OVER the spectators, the plane that really sticks in my memory though is the Fairey Delta flown by Peter Twiss which smashed the 1000mph barrier with a speed of 1132mph, no less!!  

 

Your dad was a lucky bloke, R&D of anything aeronautical must be amazing, trying to make things that fooking fly!! No doubt one of many millions we owe a dept of gratitude to. My own grandfather was an (acting) squadron leader in the military intelligence during WW2, he had loads of fascinating photos from recon missions which he used to analyse and then plan both strategic bombing missions from, as well as tactical strikes on special targets like ships in the Med.  

Edited by Nev, 25 November 2017 - 11:23 AM.

[Madmitch]

 

Fantastic!!  My father spent WWII as Chief Draughtsman at Fairey Aviation, moving to High Duty Alloys right at the end of the war.  At HDA he was involved in the development of the early high temperature alloys, necessary for the transition from centrifugal flow gas turbines to axial flow gas turbines.  I still have two prototype turbine blades on my desk here, forged but still with their sprue around the edges.  We used to go to Farnborough every year on dad's Trade Pass, amazing time with fantastic low level displays OVER the spectators, the plane that really sticks in my memory though is the Fairey Delta flown by Peter Twiss which smashed the 1000mph barrier with a speed of 1132mph, no less!!  

 

Your dad was a lucky bloke, R&D of anything aeronautical must be amazing, trying to make things that fooking fly!! No doubt one of many millions we owe a dept of gratitude to. My own grandfather was an (acting) squadron leader in the military intelligence during WW2, he had loads of fascinating photos from recon missions which he used to analyse and then plan both strategic bombing missions from, as well as tactical strikes on special targets like ships in the Med.  

 

That sounds pretty interesting too, another unseen but vital contribution that we should remember with gratitude.  I once had a chap working for me who had been at Rolls Royce before the war working on Merlins.  When the war broke out he thought he would be drafted into the RAF to carry on as an engine fitter on Merlins but no, he went to Coastal Command and was retrained as an Airframe Rigger!  

[fiveoclock]

You cant beat a two stroke triple with spannies on it

 

Edited by fiveoclock, 25 November 2017 - 05:18 PM.

[allsteel]

Never gave more than 300 brake in na form but those rx7 rally engines did it for me. A few fitted them into Escorts and the noise through the forests was incredible. The rally rotaries made a helluva noise and you literally needed to follow them with a fuel churn when they were supping through a huge Weber on an ida manifold. What a  racket.

[Madmitch]

What about the 1.5litre V16 supercharged BRM of the late 40s to early 50s?  That is truly awesome, it was said that two of those on the grid drowned out all the other cars there.  Several good bits of film on You Tube and essential listening!  

[Nev]

What about the 1.5litre V16 supercharged BRM of the late 40s to early 50s?  That is truly awesome, it was said that two of those on the grid drowned out all the other cars there.  Several good bits of film on You Tube and essential listening!  

 

Yea, very very revvy. Imagine the size of those tiny cylinders.

 

I wonder why that sort of tiny cylinder engine isn't more popular now, as they certainly made huge power.  

[Madmitch]

Good question and I don't know the answer either.  Back in 1968 I had an S800 Honda, 791cc and 71.5bhp @ 8,500 rpm and safe to 12,000, roller bearing bottom end, dohc and four Keihin carbs, it was a jewel of an engine.  You could buy three tuning kits from Honda, a reverse megaphone exhaust, bigger carbs and different cams, if you fitted all three kits you had full race spec.  Loved going through the Hyde Park Underpass at zillions of revs with the windows open...............!!  I suppose done today you would need lots of cylinders to get sufficient capacity and that makes it an expensive engine whereas most manufacturers today simply stick a great big blower - or two - and rely on loads of boost to do the job. 

[KurtVerbose]

Nev - did you see many F104 crashes? It was known in the Luftwaffe the 'widow maker' - 110 pilots killed. Very unsuitable aeroplane for Northern Europe, bought for political reasons.

 

 

As for the J79, impressive for the numbers they made it in and the variable stators. It was powerful for its weight because it was a single spool engine, but this did make it quite thirsty. It was also initially quite a smokey engine.

 

Rather than the school boy thrill of noise, flames, smoke etc, have a look at this: -

 

 

It's a Rolls Royce Ultrafan - a test engine for technologies to be ready around 2025. It has a compression ratio of 70:1, a 15:1 bypass ratio, and turbine entry temperatures of +1600°C. It also has a gearbox between the turbine and the massive carbon/titanium fan. They've already tested this gearbox at 70,000 bhp, and will take it up to 100,000 bhp.

 

 

I like these modern, high bypass ratio engines for the oposite reason you like the J79. They're quiet and efficient.

 

As for tiny cylinder engines, they have both high friction and low thermal efficiency. They're also expensive, and often heavy and harder to package. If you look through formula one when there was more freedom of engine configuration it was often not the engine with the most cylinders that won, or even the most powerful engine.

[Nev]

Yup, I knew all about the F104 crashes, we used to joke about it, but thankfully I didn't witness or hear of any whilst I was there. Ultra high wing load on the F104, when you stood next to one it was hard to imagine how it would even take off under mach 1! Also the pilots had to be under a certain size (something like 1m75) or they'd lose their knee caps when they ejected.

 

Good points about the small cylinder engine, I understand them, but the results of those BRM engines were pretty amazing in their day.

 

Have/do roller bearings exist and are they viable for big ends on con-rods? I expect those and crank roller bearings would help a lot assuming you could make them heavy duty enough to cope. Mind you, with lots of tiny pistons you only need to make tiny torque, so the con-rod bearings would see fairly low stress presumably.

 

Imagine a V or H 16 based on a race 400cc cylinder bike's cylinders, with a huge supercharger pushing out 50 Lbs.... Or even better a flat 16, for ultra low CoG.

 

 

 

 

 

 

Edited by Nev, 28 November 2017 - 08:10 PM.

[fiveoclock]

Talking of engines and planes I went to an auction today to buy some furniture to restore and they had this which I have bid on

 

https://www.tooveys....gine-crank-case

 

which as well as what they say had stamped on it also had Buick on it. 

 

It came from a historical crash site of one of these, a Curtiss P40

 

 

Only the ally bits left, the bolts and liners had rusted away

Edited by fiveoclock, 28 November 2017 - 08:18 PM.

[Nev]

Just looked the BRM V16 up:   780 HP @ 13,000 RPM and 72 Lbs of boost... all in just a 1.5 Litre engine !!!  Every one of those figures is mind bending.

 

 

 

 

Edited by Nev, 28 November 2017 - 08:44 PM.

[hairy]

Merlin does it for me

[KurtVerbose]

Here's a J79 on full reheat, turn up the volume and feel your spine tingle:

 

 

Actually Nev, that's almost certainly not a J-79. One F-16 was fitted with a J-79 with the idea of selling it to countries at a cheaper price than the standard engine. You can read up on it here - http://www.f-16.net/..._article12.html.

 

Standard F-16 engines were the Pratt & Whitney F100 and the General Electric F110, both 2 spool turbofans, one of which is likely to be in that video.

 

This is a J-79 on full afterburner, and you can see it's quite a different engine.

 

[KurtVerbose]

Anyway, how about 1000 x the thrust of the J-79?

 

The F1 engine in the Saturn V moon rocket.

 

[Nev]

That'll teach me to trust internet links on FarceBook !