Range + ETOPS of a Citation X

[GVFlyer]

Dassault

You know that Serge' Dassault tried to put the 50 out of production, but it had such a loyal customer base that the customers wouldn't let him, hince the 50EX. Falcon has had their share of problems with the TFE 731's. The 900 initially had problems with reduction gearing causing resonance and fan cracks. Then there were the problems with the carbon seals which they fixed, but then forgot to fix on the -40 and -60 engines for the 50EX and the 900EX. However, they had bigger problems on those engines in that the number 4 bearing journals were improperly drilled so they were not oiling properly. Subsequently, all the cases had to be cracked to fix the problem. Statistically, you are still more likely to arrive single engine in a three-holer Falcon than you are in the the Rolls-Royce powered Gulfstream. If three engine aircraft were a good idea, somebody besides Dassault would make them. There is an immediate 50% increase in maintenance costs when you have three engines doing the work of two. Falcon has realized this, their newest product will have two engines.

Having said all this, I've long thought that the Falcon was a great airplane in search of a great engine - they sure are sweet to fly!





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[banned username 2]

Actually the 50EX has -40 engines and the 900EX has -60 engines...

I think statistically you are more likely to end up "Single Engine" in a two engine airplane, because in a 3 engine airplane it would require a double engine failure...

I THINK what you meant is statistically you are more likely to loose an engine in a 3 engine plane than a 2 engine plane... but then again, no big deal, a single engine failure isn't even on the Emergency Checklist... it is on the Abnormal Checklist!

And by the way, their "Newest Product" will have THREE engines... the Falcon 7X.... looks like a very overgrown 900EX, but with greater sweep angle on the wings... but still 3 engines!

 

[GVFlyer]

Granted.

I meant that because the Allied Signal TFE-731's fail at a rate greater than twice as often as the Rolls Royce's that you are statistically more likely to loose two of the TFE-731's than you are one of the Rolls.

This is easy to understand. At mid-ocean, the BR-710's on the GV are running around 88-89% on both LP and HP. The fastest spool on the engine is turning around 11,000 rpm. The engine is derated to 14,750 pounds of thrust from a family of engines designed to produce 22,000 lbs. It's loafing.

The TFE-731 engine started life as an APU for the DC-10. It has had to grow significantly since it's original design. In most applications, it's trimmed up to 101.5% and it's fastest spool is spinning at over 40,000 rpm. Keep in mind that internal pressures are a squared function of rotational velocities. It's running hard.

The newest product I was referring to is the 2000EX which has flown and will be delivered with two PW308C's once certified. It's interesting to note that they have abandoned the GE 738's in this growth derivative of the 2000.

It will be interesting to see if Dassault makes the Falcon 7X. I hope they do - competition improves the breed, but they have backed out of this market once before.