G550 Single engine take off
The dynamic Vmc would not come into play -- and if thrust were modulated carefully so as to maintain directional control then it is possible or at a heavier weight then the static Vmc would matter---but the TO field length requirement due to the reduced thrust [from having to worry about Vmc] (and you would have to be light-see above and below) if not you'd blow the fuse plugs at tire speed limits---
DP. Davies mentions that this feat was tried in a few twins as a 'circus trick' so try it in the sim but you have to be deft about it,...as an operational technique
single engine TO's are best for F-16's
PA
DP. Davies mentions that this feat was tried in a few twins as a 'circus trick' so try it in the sim but you have to be deft about it,...as an operational technique
single engine TO's are best for F-16's
PA
3Reds,perhaps you`d better re- read what you have written when you are sober !!
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If just one engine will get you off airborne and climbing safely from a V1 cut then why on earth would it not get you from threshold to V1? The answer is it would. So, keep directional control and runway length permitting...
I'd also recommend amending the take off brief to state "in the event of an engine failure before or after V1, stopping would be grand"
if not you'd blow the fuse plugs at tire speed limits---
Whilst it may be possible, technically, it's one of those "so why would you want to do that?" questions!
Typhoid I was jnot even dreaming of stopping
forget about the brakes,...I mean If you are light Vmc will have to be crossed at "reduced thrust" --so in that case acceleration to a rotation speed ----will be field length limited
However if you are slightly heavier as to avoid a Vmc situation then although full thust can be had quicker---- the acceration to Vr may be so that you would have no choice but to exceed the tire speed limits whcih also melts the fusible plugs
Note:--- there's really no valid 'vee speeds' for this scenario as this is sooooo far off of any certifaction scheme that all performance figures and assumption are effectively invalidated,...and these speed regress to beings just advisory,...like V2----think about it
PA
forget about the brakes,...I mean If you are light Vmc will have to be crossed at "reduced thrust" --so in that case acceleration to a rotation speed ----will be field length limitedHowever if you are slightly heavier as to avoid a Vmc situation then although full thust can be had quicker---- the acceration to Vr may be so that you would have no choice but to exceed the tire speed limits whcih also melts the fusible plugs
Note:--- there's really no valid 'vee speeds' for this scenario as this is sooooo far off of any certifaction scheme that all performance figures and assumption are effectively invalidated,...and these speed regress to beings just advisory,...like V2----think about it
PA
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When you go into a simulator, ( at least at FSI) the certification data used are displayed in the form or the airframe s/n that was used for these said data.
Data collected are the one's available out of the flight testing envellope basically for a transport aircraft ( Vd to Vmca and -1g o 2,5g), the aerodynamics return feelings are then fine tuned in the sim by people who flew he aircraft for real. ( exemption to this rule are FBW aircrafts where the modulation of feedback is done with other means, but still requires a 'check flight')
As a consequence, if the data do not include an all engine out at FL490, what you will get is a pure mathematical extrapolation of the aerodynamic law, nothing else.
As for an engine out take off from brake release, it is obviously doable if the runway is long enough, Vmcg has nothing to do in here ( cf definition of it , the critical engine is made suddenly inoperative, the other(s) one at take off power and you have to parrallel the track using only aerodynamics ( no nswsteering) ). So smoothly adding power should do the trick.
The above mentionned experience of a C550 pilot trying to windmill start an engine on the runway, is all together another story.
You can experience whatever you want in the sim, but if it is not in the AFM, it is BullS_h_i_t.
PS. If you have spare time in the sim, practice all engines go around, and noie abatment procedures
Data collected are the one's available out of the flight testing envellope basically for a transport aircraft ( Vd to Vmca and -1g o 2,5g), the aerodynamics return feelings are then fine tuned in the sim by people who flew he aircraft for real. ( exemption to this rule are FBW aircrafts where the modulation of feedback is done with other means, but still requires a 'check flight')
As a consequence, if the data do not include an all engine out at FL490, what you will get is a pure mathematical extrapolation of the aerodynamic law, nothing else.
As for an engine out take off from brake release, it is obviously doable if the runway is long enough, Vmcg has nothing to do in here ( cf definition of it , the critical engine is made suddenly inoperative, the other(s) one at take off power and you have to parrallel the track using only aerodynamics ( no nswsteering) ). So smoothly adding power should do the trick.
The above mentionned experience of a C550 pilot trying to windmill start an engine on the runway, is all together another story.
You can experience whatever you want in the sim, but if it is not in the AFM, it is BullS_h_i_t.
PS. If you have spare time in the sim, practice all engines go around, and noie abatment procedures
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Data collected are the one's available out of the flight testing envellope basically for a transport aircraft ( Vd to Vmca and -1g o 2,5g), the aerodynamics return feelings are then fine tuned in the sim by people who flew he aircraft for real. ( exemption to this rule are FBW aircrafts where the modulation of feedback is done with other means, but still requires a 'check flight')
As a consequence, if the data do not include an all engine out at FL490, what you will get is a pure mathematical extrapolation of the aerodynamic law, nothing else.
As a consequence, if the data do not include an all engine out at FL490, what you will get is a pure mathematical extrapolation of the aerodynamic law, nothing else.
JAR-STD-1A and the equivalent FAA and ICAO sim QTG (Qualification Test Guide) standards define the test data required for a qualified device. You might be surprised at how little there is required (although a good sim builder will use more than the min).
And not all tuning is done appropriately - in at least one case I know of, the sim was tuned to someone's perception of how the aircraft 'should be', unfortunately not taking into account the actual data showing how it really is.
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The sims I know, have data up to Vd, especially if the design has 'interesting characteristic beyond Mmo ( neutral pitch at best lol). Might not be all manufacturers...
Without wishing to stir up a hornets-nest of disapproval, I have done a single-engine take-off in a B.747-400 simulator. Empty (ZFW c. 180T), 10T fuel, Doha RWY 34, (15,000ft) ISA still air. I think I used F.10, although I can't really remember.
Numbers 1, 2 and 4 were shut down. The thrust on No.3 was gingerly increased. It took about 1/3rd of the runway to get above 80kts, due to directional problems. Eventually, about 1/2 to 2/3rd down the runway, I was able to apply full thrust and got airborne just before the end.
I climbed at about 300ft/min to 1500ft and landed at Bahrain.
What does this prove? Nothing really, except it was a lot of fun and increased my already high level of respect for the 747.
Now I'm going to give you all the benefit of the doubt and assume that my readers are intelligent enough to know that I'm not advocating anything similar in the real world. I won't reply to any 'What were you thinking of?' style replies. So there.
Numbers 1, 2 and 4 were shut down. The thrust on No.3 was gingerly increased. It took about 1/3rd of the runway to get above 80kts, due to directional problems. Eventually, about 1/2 to 2/3rd down the runway, I was able to apply full thrust and got airborne just before the end.
I climbed at about 300ft/min to 1500ft and landed at Bahrain.
What does this prove? Nothing really, except it was a lot of fun and increased my already high level of respect for the 747.
Now I'm going to give you all the benefit of the doubt and assume that my readers are intelligent enough to know that I'm not advocating anything similar in the real world. I won't reply to any 'What were you thinking of?' style replies. So there.
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Still Albatross, I think that was a Sabreliner somewhere in the US.
We tried it in the old C550 in Le Bourget some 10 years ago and we could get airborne without really big problems.
We tried it in the old C550 in Le Bourget some 10 years ago and we could get airborne without really big problems.
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First of all, I am NOT a qualified pilot, though I have done a lot of flying ( I'm an aerial photographer, first for BAe now freelance ) - often used as an unofficial autopilot, sometimes given a go for more exciting flying.
I used to work mainly with Test Pilots of the highest calibre ( by calibre I mean standard, I can only think of one who should have been shot out of a gun ) - I'm damn sure you'd be sent out with a kick if you suggested taking off a twin / multi on one engine.
They'd happily do it on a sim', probably without drawing breath, but in real life losing an engine ( ie one was rather counting on more ) is an emergency, usually resulting in the aircraft staying on the ground, even if beyond the runway - at the airfield I worked on in earlier days, Dunsfold, there were raisable barriers at each end.
This came about partly because the main A281 Guildford - Horsham road runs along the Eastern end of the runway.
In the 1970's an HS125 was taking off, piloted by John Cunningham.
It suffered a multi bird strike, snuffing both engines, and was pancacked into the next field; all occupants walked away, very sadly it turned out that another pilot's wife along with several children had parked to watch the aircraft - all were killed.
As for single engine take-offs, it's deliberately putting oneself in an emergency situation ! I can't help thinking of the early days of Gnat / Hawk training, when the instructor would deliberately shut down the engine on finals, " Ha, let's see how you cope with that one ! "
Strangely enough, if the student didn't cope perfectly, they crashed.
After a while it emerged there might be a flaw in the training policy...
I used to work mainly with Test Pilots of the highest calibre ( by calibre I mean standard, I can only think of one who should have been shot out of a gun ) - I'm damn sure you'd be sent out with a kick if you suggested taking off a twin / multi on one engine.
They'd happily do it on a sim', probably without drawing breath, but in real life losing an engine ( ie one was rather counting on more ) is an emergency, usually resulting in the aircraft staying on the ground, even if beyond the runway - at the airfield I worked on in earlier days, Dunsfold, there were raisable barriers at each end.
This came about partly because the main A281 Guildford - Horsham road runs along the Eastern end of the runway.
In the 1970's an HS125 was taking off, piloted by John Cunningham.
It suffered a multi bird strike, snuffing both engines, and was pancacked into the next field; all occupants walked away, very sadly it turned out that another pilot's wife along with several children had parked to watch the aircraft - all were killed.
As for single engine take-offs, it's deliberately putting oneself in an emergency situation ! I can't help thinking of the early days of Gnat / Hawk training, when the instructor would deliberately shut down the engine on finals, " Ha, let's see how you cope with that one ! "
Strangely enough, if the student didn't cope perfectly, they crashed.
After a while it emerged there might be a flaw in the training policy...
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Purely in the name of pprune research just done it in the sim for the 680, 70% N1, NWS until the rudder worked the power to T/O, F15 got off in 6000ft comfortably.
The NWS is the key turned it into a non event - very straightforward
The NWS is the key turned it into a non event - very straightforward
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And if you did that deliberately in real life, and even survived,
you'd be called a...........
you'd be called a...........
Purely in the name of pprune research
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Like little boys and girls why can't we just play sometimes
, tasked herocially with the recovery of some fine bizjet by a banking corporation from some tinpot dictator who had decreed that both ignitors be removed and taken from one of the engines. My trusty FO (who'd already had the incap tap on the shoulder) had been........"left at home for this one" as it was far too dangerous........Of course I managed to get it off just as the sand and gravel runway dipped into the ocean in true "A-Team" fashion, the instructor was tapping his pen against the back of my seat to simulate the small arms fire......
And then the noise of the motion coming off and the health and safety beeping of the gantry coming down sort of spoiled the moment
Right im off to find the wifes mascara to see what I look like with a moustache......
I can't help thinking of the early days of Gnat / Hawk training, when the instructor would deliberately shut down the engine on finals, "Ha, let's see how you cope with that one !"
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Yes,
It was really done in training, throttling back rather than shutting off completely the Hawk adour ( sorry, I should have been clearer ); as you know, with the spool-up time of jets, this still led to a few nasty accidents.
I understood this was a snag to overcome ( not particular to the Hawk ) when the U.S. Navy took on the T-45 Goshawk version, and the Red Arrows + company demonstrator G-Hawk ZA101 have modified throttles for faster mid-range response, probably the T-45 too, but there are a lot better qualified people here to comment than myself.
It was really done in training, throttling back rather than shutting off completely the Hawk adour ( sorry, I should have been clearer ); as you know, with the spool-up time of jets, this still led to a few nasty accidents.
I understood this was a snag to overcome ( not particular to the Hawk ) when the U.S. Navy took on the T-45 Goshawk version, and the Red Arrows + company demonstrator G-Hawk ZA101 have modified throttles for faster mid-range response, probably the T-45 too, but there are a lot better qualified people here to comment than myself.
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Back in the days of the early jets there was one occasion when they deliberately flew a FH-1 Phantom (not the big F-4, but a much lighter early Navy straightwing jet) on one engine only. Might have been its first flight IIRC.
Hopefully someone else has more complete recall of this incident which will save me raking through my extensive reference collection for the details.
It was at Edwards or China Lake I think. Reason? They were so keen to fly it they just couldn't wait for the other engine to arrive!
Hopefully someone else has more complete recall of this incident which will save me raking through my extensive reference collection for the details.
It was at Edwards or China Lake I think. Reason? They were so keen to fly it they just couldn't wait for the other engine to arrive!