The Battle Of The Supercharger England & Germany.

[II./JG27_Rich]

The first part is all about race cars and the second half is, you guessed it all about the Spitfire and Messerschmitt 109. Gunther Rall even has a chat with Robbie Coltrane.

 

http://www.youtube.com/watch?v=gwU3bfaLhJ4

[Freycinet]

Thanks, looks very interesting. A piece of technology I don´t know enough about... I´ll give it a look!

[II./JG27_Rich]

Thanks, looks very interesting. A piece of technology I don´t know enough about... I´ll give it a look!

Yes take a look. There is a huge difference between the two sistems. 109 and Spitfire's

[mazex]

Thanks for sharing! I was almost waiting for a clip from the 1937 Donington GP with the Mercedes W125 (Supercharged V8:s with 595 hp in 19 friggin 37 ).

 

I just love this article by an English journalist that witnessed it (from http://en.wikipedia.org/wiki/1937_Donington_Grand_Prix)

 

"Away beyond the woods we heard the approaching scream of a well-tuned E.R.A. and down the winding slope towards us came Raymond Mays. He changed down, braked, skirted round the Hairpin and was gone. "There's the winner," remarked one of my friends. "Knows this course backwards." Half a minute later came the deeper note of a 2.9-litre Maserati, and "B. Bira" (Prince Birabongse of Siam, Mays’ nearest rival and a new star in the racing firmament) shot past us, cornering with that precision which marked him as the master he was. "Or him," said another. We waited again. Then they came. Far away in the distance we heard an angry, deep-throated roaring – as someone once remarked, like hungry lions impatient for the arena. A few moments later, Manfred von Brauchitsch, red helmeted, brought a great, silver projectile snaking down the hill, and close behind, his teammate Rudolf Caracciola, then at the height of his great career. The two cars took the hairpin, von Brauchitsch almost sideways, and rocketed away out of sight with long plumes of rubber smoke trailing from their huge rear tyres, in a deafening crash of sound. The startled Pressmen gazed at each other, awe-struck. "Strewth," gasped one of them, "so that's what they're like!" That was what they were like."

[II./JG27_Rich]

Interesting

[III/JG53Frankyboy]

i like that my modern car still has a supercharger (compressor) and not a turbocharger

that makes 333PS from a 3 l V6 engine

Edited August 22, 2013 by Frankyboy

[Freycinet]

A fun watch, tho a bit short on technical details... :-)

[Heywooood]

got CHARTZ?

[79_vRAF_Friendly_flyer]

Thanks for the link! What a, what is the right word, delightful program!

[Trooper117]

Rather, old boy!

Good stuff, and loved the old cars too.. that's when men were men  

[Dooga]

with turbocompressor you can fly high but with injectors you can pull negative g

 

You are joking, right? Never quite sure with any of your posts...

[SCG_Neun]

Good find Richie....Enjoyed it a lot....

[Dooga]

they mentioned it in 18:50 spit uses not injectors but works by gravity so in negative g...

 

i think mercedes compressors are mechanically linked to the engine axle while rolls royce uses the exhausts fumes 

 

none should be more eficient but again 109 was better engineered at least for the lack of injectors in spits

 

 

That's why what the Merlin is using is called a turbocharger, while the Mercedes engine uses a compressor. Different concepts.

 

Well, have fun flying inverted at 3000ft on a naturally aspirated engine - while the opposing air force blows by at 25000ft, three times as fast as you down between the trees...  

 

The only marginally useful thing the ability to pull negative load gives you is a first knee-jerk reaction evasive maneuver, *if* your opponent can't follow you easily because his engine would cut out (as was the case between earlier Spit Marks and the 109). No one pulls negative gs if he doesn't have to as it's less aerodynamically inefficient (on most planes) and just plain impossible to endure for a human pilot. 

 

Btw the engine cutout problem on negative loads in the Spitfire was initially not solved by adding fuel injection, but by putting a small metal disc (for fuel flow restriction) into the carburetor (refer to http://en.wikipedia.org/wiki/Miss_Shilling's_orifice)

 

I'm not saying that fuel injection isn't good - it's brilliant - but in an aircraft engine it's simply irrelevant when compared to the benefits of supercharging.

Edited August 23, 2013 by Dooga

[DD_bongodriver]

The Merlin is supercharged not turbocharged

[Dooga]

At altitude, a naturally aspirated piston engine will always loose to a charged one, period - there simply isn't enough air available. If you want to experience that yourself, go somewhere really high and work out for a bit (or fly a piston plane at altitude).

 

All of these engines were four stroke, except for a couple of Jumo Diesels. I've never heard of a two stroke engine with the amount of power we're talking about here (except for very large and heavy ones in ships). I'm not an engineer but I assume at the power to weight ratios we're looking at, a two stroke would simply melt.

Edited August 23, 2013 by Dooga

[Dooga]

The Merlin is supercharged not turbocharged

Sry you're right of course - I was reading about the turbonormalized IO-550 just now, which probably got me confused :-)

[79_vRAF_Friendly_flyer]

Coltrane has a program on the two-stroke too (just looked through the lot), and I don't think it is suited for aeroplanes.

[Dooga]

well actually 2 strokes have a much better weight-power ratio and so it melts an excesively charged one, in the end limits temp

 

but im talking of fast engines like a small motorbike not marine ones which are very slow

Which is precisely why I'm saying they would probably melt. Heat dissipation is a problem even for small two strokes, and when we're talking 2000hp aircraft pistons, even four strokes (which only produce heat every fourth stroke) and are comparatively large have trouble getting rid of all the heat. If water injection could cure this, I'm pretty sure we would have seen large two stroke pistons at the end of the piston era, there were many extremely clever engineers around back then...

 

P.S.: Power to weight ratio doesn't help you if there is not enough oxygen to burn - no air, no power.

 

Over and out...

Edited August 23, 2013 by Dooga

[II./JG27_Rich]

Thanks for the link! What a, what is the right word, delightful progra

 

Coltrane has a program on the two-stroke too (just looked through the lot), and I don't think it is suited for aeroplanes.

Yes I watched the Two Stroke, Steam, V8 and Supercharger. My only disapointment was he had the Mopar Hemi demonstrated hooked up to an air raid siren. The 392 Hemi dominated the Drag Race circut for years in the 60s and 70s. It's actually a stronger engine than the 426 Hemi.

[GP*]

That's why what the Merlin is using is called a turbocharger, while the Mercedes engine uses a compressor. Different concepts.

 

Well, have fun flying inverted at 3000ft on a naturally aspirated engine - while the opposing air force blows by at 25000ft, three times as fast as you down between the trees...  

 

The only marginally useful thing the ability to pull negative load gives you is a first knee-jerk reaction evasive maneuver, *if* your opponent can't follow you easily because his engine would cut out (as was the case between earlier Spit Marks and the 109). No one pulls negative gs if he doesn't have to as it's less aerodynamically inefficient (on most planes) and just plain impossible to endure for a human pilot. 

 

Btw the engine cutout problem on negative loads in the Spitfire was initially not solved by adding fuel injection, but by putting a small metal disc (for fuel flow restriction) into the carburetor (refer to 

<a data-ipb="nomediaparse" data-cke-saved-href="http://en.wikipedia.org/wiki/Miss_Shilling" href="http://en.wikipedia.org/wiki/Miss_Shilling" s_orifice"="">I'm not saying that fuel injection isn't good - it's brilliant - but in an aircraft engine it's simply irrelevant when compared to the benefits of supercharging.

 

Incorrect.

 

Negative Gs certainly have their place in air to air combat. The ability of an aircraft's systems (whether it be the engine's fuel system, oil system, etc) to withstand negative Gs for at least a brief period of time can be hugely important. 

 

Firstly, don't underestimate the ability to bunt over to escape an enemy -- a half roll is time consuming relative to bunting, and, once inverted, you have to maintain positive G on the aircraft to keep the engine running (what if the enemy sees you complete your half roll and then starts to extend, rather than pull through as in a split-s maneuver? time to roll over again... What if he pulls up aggressively into you just as you complete your half roll? The heading crossing angle he can generate at this point could be considerable, and turn a clearly offensive picture into more of a neutral situation). 

 

Additionally, negative Gs aren't necessarily inefficient. In many aircraft, unloading to 0 to -0.5 Gs is an excellent way to accelerate back up to a good maneuvering / fighting airspeed (note that I'm not saying "bunt to -4 Gs" -- that would, in fact, be inefficient and excessive). 

 

What if you recognize excessive closure while pulling lead for a gun attack? A push over to lag while you drive to the bandits turn circle could save you an overshoot, versus having to quarter roll and then drive.  

 

And what about negative gun jinks? Not only are they effective, but they can be very disorienting for an offender. 

 

Rather than continue to list uses, however, all I'm trying to say is that fuel injection, and therefore the ability to handle negative Gs, is a big deal. It's not just a last ditch maneuver of insignificant importance. 

 

And yes, you're right -- fuel injection is brilliant. As is supercharging an engine. But one doesn't make the other irrelevant. 

[II./JG27_Rich]

Also 109s were a dry sump engine with the oil tank right behind the spinner so there was no problem with oil pick up either when you flew upsidedown

Edited August 24, 2013 by Richie