Why do Dassaults have 3 engines?
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It is all about aerodynamics, the exhaust of the third engine and the design of the tail section induce a laminar flow with virtually no parasite drag. The work on the Falcon 2000 for the computation of the area_ruling that governs the aft fuselage was horrendous.
Therefore, with the the same amount of thrust you are saving around 30%, just in aerodynamic excellence. On a Falcon you do not have unnecessary feathers.
Now a cabin size stand point , the 7X could have been better, but since the fuselage certification is a big chunk in a program; Dassault is still using the grand fathers rights of the Falcon 20 certification....only 40 years old...bugg_er.
Now they want to go all electrics...a twin-engine electric...;sounds like a R/C model...
Therefore, with the the same amount of thrust you are saving around 30%, just in aerodynamic excellence. On a Falcon you do not have unnecessary feathers.
Now a cabin size stand point , the 7X could have been better, but since the fuselage certification is a big chunk in a program; Dassault is still using the grand fathers rights of the Falcon 20 certification....only 40 years old...bugg_er.
Now they want to go all electrics...a twin-engine electric...;sounds like a R/C model...
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It is all about aerodynamics, the exhaust of the third engine and the design of the tail section induce a laminar flow with virtually no parasite drag. The work on the Falcon 2000 for the computation of the area_ruling that governs the aft fuselage was horrendous.
Therefore, with the the same amount of thrust you are saving around 30%, just in aerodynamic excellence. On a Falcon you do not have unnecessary feathers.
Therefore, with the the same amount of thrust you are saving around 30%, just in aerodynamic excellence. On a Falcon you do not have unnecessary feathers.
All electric? I don't see how thats possible in long range planes.
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The name of the pepole you want to speak with is CATIA; with a couple of bundles for aeroynamic and visco elasticity modules. Aera ruling is more trial and errors than a true science, nethertheless results are proven indeed...
For the electric gizmo; they only speak about flight controls, brakes, etc.. Not the engines...It was initially Rolls Royce, but apparently some last minutes with the silvercrest (snecma) are giving a new deal.... Let us see what comes out of the box... Hopefully it won't have winglets....
For the electric gizmo; they only speak about flight controls, brakes, etc.. Not the engines...It was initially Rolls Royce, but apparently some last minutes with the silvercrest (snecma) are giving a new deal.... Let us see what comes out of the box... Hopefully it won't have winglets....
Over oceans or remote areas, three or four engined planes do not have to divert upon loss of an engine, they can continue on 2/3 to their destinations, if 1/2 cruise ceilings are above the terrain and no other system emergency dictates a divert. ETOPS or not, an engine failure on a twin over water or Siberia has a real problem. See numerous threads about BA going on three from LAX to LON, Manch, actually.
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It would be interesting to see if the the drag caused by the rudder counteracting the assymetric thust after failure of an out board would be more, or less than, the additional drag caused by the loss of laminar flow around the tail after the failure of the centre engine. In either case, there are scenarios in which completion of a flight with an engine out will burn very little, if any, extra fuel. (With the FA50, at least).
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ETOPS = Extended twin engine ops (DA50, 900 & 7X not twins thus EROPS)
EROPS = Extended range ops (multi i.e. more than 2 engines)
EROPS = Extended range ops (multi i.e. more than 2 engines)
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Well at the end of all this discussion it all comes down to one thing. Europeans design their aircraft,cars etc for the job they have to achieve using all the very best technology available or indeed develope technology for the the equipment. American design rules are as follows design something big enough to fit overweight people in along with their over-inflated ego's, design it larger than it needs be so that the machine helps to further inflate already overinflated ego, then discover that said machine won't fly. Solution put a bigger engine on it!! ( just like their poorly designed cars that the world no longer wants to buy).
Dassault builds some of the best machines in the sky, having flown their military products and civil products I speak for both. Beautiful to look at even better to fly and cost effective to operate. Subttle strong and capable something US designers can only dream of!
Dassault builds some of the best machines in the sky, having flown their military products and civil products I speak for both. Beautiful to look at even better to fly and cost effective to operate. Subttle strong and capable something US designers can only dream of!
Last edited by unablereqnavperf; 25th Jan 2010 at 14:15.
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American design rules are as follows design something big enough to fit overweight people in along with their over-inflated ego's, design it larger than it needs be so that the machine helps to further inflate already overinflated ego, then discover that said machine won't fly. Solution put a bigger engine on it!!
That being said, I flew Falcon 50/50EX/900B/900EX and loved them. I also took a demonstration flight in a straight 900 at MGTOW, in the summer. We didn't buy it.
As for the rest of your remarks; well, there is just no accounting for rudeness, is there.
Back to a civil discussion on the subject. We had a fly off between the G-IVSP and the 900EX. We chose the 900EX for one primary reason, the 900EX can, under winter temperatures/conditions in good weather go non-stop from Aspen, Colorado to London, UK. The G-IVSP could not under any condition.
Also flying trans Pacific routes, having that third engine was/is great peace of mind. (There's a lot of real dark water at night between Hawaii and Guam.)
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I know its just my opinion but I always felt the falcons looked like old aircraft.. I totally agree their performance is impressive, but they are NOT beautiful machines.. The 7X is the best so far but it just longs slightly off somehow, and the 900 looks like a retarded tristar.. A little short fat eye sore
Global got a pretty machine, the 550 is still stunning and the 650 is just gorgeous..
Global got a pretty machine, the 550 is still stunning and the 650 is just gorgeous..
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Oh well, as they say, beauty is in the eye of the beholder.
Needless to say I disagree. Now, you take a Hawker 125, that's ugly for you.
Needless to say I disagree. Now, you take a Hawker 125, that's ugly for you.
I do hope our American friends can forgive you for your unsolicited ruddeness, at least they can spell better than you.
Back to the thread,
When the question "Why has 'abc' got 3 of them?" is asked, the chorus of replies is usually "'cos two's not enough and four's too many".
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When the question "Why has 'abc' got 3 of them?" is asked, the chorus of replies is usually "'cos two's not enough and four's too many".
Why do you only fly four engine aircraft over the oceans?
Because they don't make five engine aircraft.
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Why 3 engines in the 900?
Because they could not find room for a 4th. The 900 is severely underpowered. Or maybe its just because my fat ass weighed it down? And I am not even an "American".
I used to listen to G5 pilots talk about the 3 hair driers mounted on the 900. It hurt my feelings as I thought quite highly of the plane. Now I totally understand what they were talking about. Need to change my name from DA50driver now I guess.
I used to listen to G5 pilots talk about the 3 hair driers mounted on the 900. It hurt my feelings as I thought quite highly of the plane. Now I totally understand what they were talking about. Need to change my name from DA50driver now I guess.
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From what I understand there are no straight 900s anymore. I believe that they were all upgraded to 900Bs.
Could be wrong, wouldn't be the first time.
Could be wrong, wouldn't be the first time.
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Well at the end of all this discussion it all comes down to one thing. Europeans design their aircraft,cars etc for the job they have to achieve using all the very best technology available or indeed develope technology for the the equipment. American design rules are as follows design something big enough to fit overweight people in along with their over-inflated ego's, design it larger than it needs be so that the machine helps to further inflate already overinflated ego, then discover that said machine won't fly. Solution put a bigger engine on it!!
And my peers are all sleek, otherwise the sov would be too small. Slight flaw in yer thinking, innit?
I´d vote for the best of both worlds, a Challenger 300, as room as I need it and as small as I want it if I´d have to clean it.
Still, the Falcons are the beauty queens...IMO
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Readng this thread there are few 'facts'.
First a bit of History!
3 engines vs 2 is a long debated topic but the issue started with relaibility. Long ago aircraft generally had three engines - 727, Trident, DC10, L1011 then relaibility improved and one engine dropped off. But its not just engine relability its system relaibility/redndancy that is as crucial. Engines often fail due to systems!
2. The Falcons engines are three lower powered - fact. Its got three Lear45 engines screaming their little heads off! The engines on the 900 (&7X for that matter) do not have an airline application which builds relaibility, lowers shutdown rates etc. Take for example the G4's Spey or the Challengers 604 CF34, the later having over 50 millions. The GV/GEX has the RR BR700 series also on an airliner - albeit defunct now.
3. Systems are probably more crucial. Check the latest level of redundancy in the hyrdaulics. electrics, fuel etc and the Falcon is lacking. Fine, set out for Maui in your 900 by all means but if these go you are as good as stuffed! The more recent aircraft have the redudancy of systems built in.
4. The infomation about the runway length/slats does not take account of the weights. Guess what the 900 is lighter - Falcon cheat with the interior - just look at the seats, small galley etc. Comparable approach speeds of the Gv and GEX prove this - GEX is 109kts and the GV is 129kts. Also you can get the GEX into & out of 4000ft. which is suicide in a GV!
Finally, Falcon have explianed to me with any satisfaction how if they have it right on the 900 and formerrly the F50 - both 3 holers, then are they wrong on the F2000 which was built to counter the 604, which is, yes you are right, a two holer....
Two is fine. Three is weight and maintenance costs.....
First a bit of History!
3 engines vs 2 is a long debated topic but the issue started with relaibility. Long ago aircraft generally had three engines - 727, Trident, DC10, L1011 then relaibility improved and one engine dropped off. But its not just engine relability its system relaibility/redndancy that is as crucial. Engines often fail due to systems!
2. The Falcons engines are three lower powered - fact. Its got three Lear45 engines screaming their little heads off! The engines on the 900 (&7X for that matter) do not have an airline application which builds relaibility, lowers shutdown rates etc. Take for example the G4's Spey or the Challengers 604 CF34, the later having over 50 millions. The GV/GEX has the RR BR700 series also on an airliner - albeit defunct now.
3. Systems are probably more crucial. Check the latest level of redundancy in the hyrdaulics. electrics, fuel etc and the Falcon is lacking. Fine, set out for Maui in your 900 by all means but if these go you are as good as stuffed! The more recent aircraft have the redudancy of systems built in.
4. The infomation about the runway length/slats does not take account of the weights. Guess what the 900 is lighter - Falcon cheat with the interior - just look at the seats, small galley etc. Comparable approach speeds of the Gv and GEX prove this - GEX is 109kts and the GV is 129kts. Also you can get the GEX into & out of 4000ft. which is suicide in a GV!
Finally, Falcon have explianed to me with any satisfaction how if they have it right on the 900 and formerrly the F50 - both 3 holers, then are they wrong on the F2000 which was built to counter the 604, which is, yes you are right, a two holer....
Two is fine. Three is weight and maintenance costs.....