Why does the Falcons have 3 engines?
Thread Starter
Joined: Nov 2003
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From: Brazil
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.
Is it for the passengers / owners feel safer?
It doesn't make sense, at least in the costs aspect.
Joined: Feb 2000
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From: CYZV
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.
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.
Joined: Nov 2000
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From: London,Bucharest...wherever...
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.
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.
Joined: Jul 2002
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From: A Marriott somewhere
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.
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.
Joined: Sep 2002
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From: La Belle Province
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.
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.
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.
Joined: Sep 2001
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From: Melbourne, Australia
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.
