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When did "Reheat" become "Afterburner" ?

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When did "Reheat" become "Afterburner" ?

Old 30th Sep 2016, 07:47
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It's an "aeroplane", Mr Bader
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Old 30th Sep 2016, 07:55
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And when did the English 'alti-meter' become the American 'al-tim-eter'?
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Old 30th Sep 2016, 08:39
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Originally Posted by NutLoose View Post


I believe the VC10 had thrust augmentation BTW with that little outlet just aft of the Baggage door ( I mean the freight one, not the crew one)
Anyone have any idea how much the thrust augmenters on the VC10 (air conditioning exhausts) added, if any, to the push of 4 Conways ?
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Old 30th Sep 2016, 08:49
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What about "Finals Three Greens" to "Finals Gear Down and Locked"?
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Old 30th Sep 2016, 08:50
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From the sources I found the original afterburner term referred to was the electromechanical component used to inject the fuel. The resultant fuel/air mix producing reheat.

Referred to as afterburner up to 1945 by AERL researchers who successfully ran the first prototype.

AERL afterburner research

Last edited by ORAC; 30th Sep 2016 at 09:02.
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Old 30th Sep 2016, 08:55
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Anyone have any idea how much the thrust augmenters on the VC10 (air conditioning exhausts) added, if any, to the push of 4 Conways ?
When I did my VC10 ground school they tried to find out to no avail.

I remember Dick Langworthy saying on an exchange he eventually had all the Americans calling the Windshield the correct term Windscreen and correcting fellow Colonials when they said it.
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Old 30th Sep 2016, 09:20
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Old 30th Sep 2016, 09:22
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Old 30th Sep 2016, 10:40
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Originally Posted by John Eacott
Now, when did "airscrew" become "propellor"?
I may be wrong, but didn't that have something to do with RAF ME in WW2 sending an urgent request for 100 airscrews for Wellingtons being misinterpreted as requiring 100 aircrews? The crews were urgently deployed, the propellers not so..
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Old 30th Sep 2016, 10:48
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Originally Posted by newt View Post
What about "Finals Three Greens" to "Finals Gear Down and Locked"?
As the F4 did not have the light system to show undercarriage status but used dolls-eye indicators instead, the call was always "final, gear down"
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Old 30th Sep 2016, 10:56
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The P-51 Mustang also had thrust augmentation, the clever design of the cooler bulge underneath, meant the heated air from the cooler not only counteracted the drag of hanging the cooler out under the fuselage, but actually produced a small increase in thrust.
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Old 30th Sep 2016, 11:33
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And when did "finals" become "final"?
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Old 30th Sep 2016, 11:43
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Why do the Americans call the ground floor the 1st floor.
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Old 30th Sep 2016, 11:51
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but actually produced a small increase in thrust.
Afraid not. What it did was reduce cooling drag. Radiator drag (gross) was about 400 pounds on the P-51, but the momentum recovery was some 350 pounds of compensating thrust, leaving an effective drag component of 50 pounds. British invention by the way, called the Meredith effect, first used on the Spitfire.
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Old 30th Sep 2016, 13:49
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Talk of the Meredith effect and the P51 in a thread about thrust augmenters/reheat/afterburners, reminded me of an old Farnborough report that would combine the threads together.
This is the summary from the report that was published in November 1943.


"Estimates of the effect of burning fuel in the radiator duct of Mustang behindthe matrix, show that a top speed increase of 45 mph, at all heights ispossible with a combustion temperature of l000C. Larger increases are possiblewith increased combustion temperatures. Loss of speed with the burners not in actionshould be negligible, and operation for 5 minutes at 1000C uses sufficientfuel to reduce the subsequent endurance by about 18 minutes."

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Old 30th Sep 2016, 14:31
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@Wander 00

It has always been "final" as it is short for "on final approach", anything else is pure hollywood
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Old 30th Sep 2016, 14:36
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that is what I was taught that on my RAF engineering courses, it does produce thrust, the only one that does as far as I am aware and to quote the designer

He recounted his tales of the design concept of the P51 and on his ideas for aerodynamics at that time that led him to believe he could build a front line fighter with a higher top speed than the Spitfire MkIX. The key to the performance of the aircraft and its high top speed, he explained, was the air scoop that swung down below the fuselage to gulp great lungfulls of air. Nicknamed the doghouse, it makes the P51 instantly recognisable from any distance and has become a design icon of the second world war.
Yet what I was unaware of until hearing Lee Attwood’s presentation was that despite hanging down into the airflow like a basking shark, the whole assembly doesn’t add any significant drag to the airframe. In fact, at various speeds, it actually provides thrust. This thing wasn’t just designed to look stunning. It had a clarity of purpose that came from many hours wind tunnel testing theories which at that time represented the cutting edge of aerodynamics.
So how didLee Attwood and the team at North Americanachieve this amazing feat? Any racing car designer will tell you that cooling an engine creates drag. The smaller the radiators, the less drag, more speed. Too small a radiator of course means that cooling becomes marginal. Many warbird fighters have very marginal cooling systems, unable to spend much time on the ground on hot days before overheating, just like a Formula One car on the grid.
The clever part of the Mustang cooling is not just in the intricately formed leading edge with its hand formed compound curves, but in the secondary section that comes after the air has entered the scoop. Nicknamed the ‘doghouse’ section, named after its shape resembling an upturned kennel, intricately shaped ramps and angles channel the air into a smaller and smaller space. As it’s forced into the smaller area, it’s forced rearwards, passing through what is effectively a choke, before being allowed to expand and pass through the radiator and oil cooler. The hot air then exits through a small flap, the size of which is continuously adjustable and creates the back pressure needed to achieve thrust. The difference in speed between the Spitfire XIX and the Mustang P51D is generally recorded as 405 vs 437 mph. Despite much discussion regarding laminar flow wings and fuselage fairings, Lee Atwood’s presentation, from the very man who designed the fighter, made it quite clear that it was the attention to detail and optimising the Meredith Effect that gave the P51 it’s high speed
P51 Mustang Meredith Effect explained by Lee Atwood, designer

CONCLUSIONS
The additional thrust of the cooling system further increases the interest for piston engines propulsion
in aeronautical field. In fact, due to the Meredith effect, it has been possible to eliminate the radiator drag and to increase the total thrust of the power-pack. Therefore, Meredith ramjet improves the total available thrust and reduces fuel consumption. Both under-fuselage/under nacelle and in-wing configurations were analyzed
https://www.google.co.uk/url?sa=t&rc...34495766,d.ZGg

Last edited by NutLoose; 30th Sep 2016 at 14:57.
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Old 30th Sep 2016, 17:44
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Would it confuse things if I confessed that I never fully understood why plenum chamber burning didn't fry the compressor ?
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Old 30th Sep 2016, 17:59
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Surely it has to be running at a lower pressure than the compressor or you would get flow reversal as in a surge, therefore would it effect the compressor? Wasn't the problem they had to do with the change of direction in the nozzle, though they had cured that before it got canned.
I take it we are talking Pegasus, that was the core engine based on the Orpheus out of the Gnat with a bypass fan nailed on the front, the fan feeding the forward nozzles and the hot end the aft ones.
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Old 30th Sep 2016, 23:31
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Why do Americans drive on parkways and park on driveways?
'Parkways' because of the extensive landscaping on the right-of-way. Long, skinny 'parks' with a road up the middle.

'Driveways' I'm not sure about, but affluent homes on extensive grounds had 'drives' leading up to them which, probably by the magic of advertising, became 'driveways' when attached to more modest houses.
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