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Why does the Falcons have 3 engines?

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Why does the Falcons have 3 engines?

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Old 10th Nov 2003, 09:36
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Why does the Falcons have 3 engines?

With the exception of the Falcon 2000, all new Falcons (as long as I know) have 3 engines. Why?

Is it for the passengers / owners feel safer?

It doesn't make sense, at least in the costs aspect.
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Old 10th Nov 2003, 11:40
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fish

I've had a P&W rep tell me it's so's you can finish a flight on two, but I suspect he was biased.
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Old 10th Nov 2003, 12:34
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It's so that they can do long range flights without having to worry about ETOPS certification
 
Old 10th Nov 2003, 18:41
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I had a Challenger rep tell me it's because Dassault fit "Garrett Grenades" but I think he was being a little unfair!
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Old 10th Nov 2003, 20:45
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It gives the fat cat that owns it a little piece of mind when out over the pond. And.....mostly because if you can afford a new Falcon, engine maintenance is not one of your worries.
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Old 10th Nov 2003, 21:28
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And why does (did?) the Lockheed Jetstar have 4?
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Old 10th Nov 2003, 22:15
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And the B-52: Eight (8)!
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Old 10th Nov 2003, 22:35
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...and the Dornier Do X had TEN!
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Old 11th Nov 2003, 03:20
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I suppose that's why those last 2, and others like them, had all those engineers on board - just to work the throttles!
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Old 11th Nov 2003, 05:26
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Gentlemen, please. Enough with the terrible jokes already. Time for a serious answer.

The Jetstar prototype was originally built for a military application with two 4800 lb thrust Bristol Orpheus engines - that were to be built under license by Curtiss-Wright - and no slipper tanks. The deal to build the Orpheus in the US fell through, and the American military were reluctant to acquire an aircraft with a foreign built engine. Lockheed went back to drawing board and added two pairs of 3000 lb thrust P&W JT12's in place of the single powerplant, added two 560 gallon slipper tanks to counter the increased fuel requirement and as they say in French "Viola!"

Trivia tidbit: The four rear mounted engines configuration Lockheed used was first proposed by Vickers in 1956, for the project that became the VC10.
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Old 11th Nov 2003, 18:35
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What's wrong with terrible jokes ?

I thought I saw a VC10 once, but it was only an Ilyushin !!!!
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Old 11th Nov 2003, 20:51
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Educated guess - at the time of the inception of the first of the Falcon trijets, the Falcon 50, the only proven light fan engine was the TFE 731 series which had a track record on the LR35/36 and 125-700 (the later 731-5 series was fitted to the Falcon 900 and 125-800).

The only other suitable contender in the power bracket for a 2 engined alternative being the ALF502 from Avco Lycoming which at the time has all sorts of teething problems which were being experienced by operators of the 146 and Challenger 600.
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Old 11th Nov 2003, 21:18
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Specnut727, that has to be the worst aviation joke I have ever read.

Made me smile

D
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Old 12th Nov 2003, 08:03
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3 Engines on Falcons

I don't know, but it feels really good to have 3 throttles in my hand. I have flown a Falcon 50 for a couple of years, and it is a wonderful airplane.

Also, if you lose one engine on a twin, you loose a lot of your excess power(which makes you climb). If you lose one of three, you lose a lot less of your excess power on a percentage basis.

The airplane has an amazing performance envelope. We operate out of a 4300 foot strip, and can legally carry 3.5 hours of fuel on a wet runway, ISA day. Off longer runways we can non-stop it to Western Europe.
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Old 12th Nov 2003, 11:29
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specnut727!! LOL -

VC10 was a thing of beauty! Sad to see her retire from airline ops as indeed I was with Tridents and my beloved 1-11's!
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Old 12th Nov 2003, 12:51
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So then the answer must be it has three engines because it has three throttles.
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Old 13th Nov 2003, 01:48
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DA50driver
Also, if you lose one engine on a twin, you loose a lot of your excess power(which makes you climb). If you lose one of three, you lose a lot less of your excess power on a percentage basis.
But since both the twin and the trijet must meet cert requirements, the worst you can ever be for FAR25 is:

takeoff first segment (gear down):
on a twin:
"positive" climb (25.121(a))
On a trijet:
0.3% climb (25.121 (a))
takeoff second segment (gear up):
on a twin:
2.4% climb (25.121 (b))
On a trijet:
2.7% climb (25.121 (b))
above 400ft:
on a twin:
1.2% climb (25.111(c)(3)(i))
On a trijet:
1.5% climb (25.111(c)(3)(ii))

So following engine failure the climb gradients are not dissimilar - which means that all other things being equal a twin will have better performance (in terms of excess thrust) when all engines are operating, which is the most common case (you hope ). So unless that 0.3% difference is make-or-break - in which case the twin won't be taking off without unloading - the twin is usually a better climber.
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Old 16th Nov 2003, 17:07
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There is a bit more than just the certification to it mad scientist. What you quote is the certification requirements. I can't think of any of the aircraft quoted above that wouldn't exceed those requirements, some by a large margin. So the difference lies in the figures actually achieved by the individual aircraft.
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Old 17th Nov 2003, 03:40
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Ripper:

No, the real answer is that it doesn't fly very well on 2 engines.
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Old 17th Nov 2003, 07:16
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...and the thrust reverser on the center engine is to make noise so you think it's slowing you down.
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