Post V1 rejected take off...yeah or neah?
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Does a clipped right side make the aircraft un-airworthy?
Whats the consequence of rejecting a takeoff at V1+5 knots?
As previous posters allude, an awful lot of variables, which is why you would make a quick snap decision of fly/nofly and then live(or not
) with that decision.
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Pug - why do you think 'a continuous use of full thrust will add to the likelihood of an RTO' ?
In corporate operations, the use of max thrust for every take off is normal...but of course we overhaul our engines at specified TBOs... in the interest of fairness, would it be prudent to use max take off power on a 25000 hr engine vs a 3500 hr one...no...but then again...if the goal here is to stretch engine overhauls out as far as possible...reduced thrust makes sense....if saving money is the chief consideration...
In corporate operations, the use of max thrust for every take off is normal...but of course we overhaul our engines at specified TBOs... in the interest of fairness, would it be prudent to use max take off power on a 25000 hr engine vs a 3500 hr one...no...but then again...if the goal here is to stretch engine overhauls out as far as possible...reduced thrust makes sense....if saving money is the chief consideration...
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Your car is in a skid ........
do you aim for a petrol station or a school yard?
no time for thought, just do it
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My views align with lomapaseo's ..
(a) whether johns7022 is/is not the same person as any other username, largely, is irrelevant. Provided he/she observes the reasonable niceties, he/she is welcome to play in the sandpit
(b) if anyone finds offense in the presence of a given participant, then one is not obligated to participate ...
(c) johns7022 proposes an extreme view which is permitted within the normal regulatory and operational processes.
(d) whether his/her proposals are good, bad, or indifferent is not the important point. Rather, the extreme views are useful to force other participants to consider their own positions critically and offer either supporting or contrary views.
.. and, of course, it is good fun.
(a) whether johns7022 is/is not the same person as any other username, largely, is irrelevant. Provided he/she observes the reasonable niceties, he/she is welcome to play in the sandpit
(b) if anyone finds offense in the presence of a given participant, then one is not obligated to participate ...
(c) johns7022 proposes an extreme view which is permitted within the normal regulatory and operational processes.
(d) whether his/her proposals are good, bad, or indifferent is not the important point. Rather, the extreme views are useful to force other participants to consider their own positions critically and offer either supporting or contrary views.
.. and, of course, it is good fun.
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would it be prudent to use max take off power on a 25000 hr engine vs a 3500 hr one....no...but then again...
@ Johns7022/SSG - I don't think you understand "creep" of hot turbine blades.
Have you ever been curious why Full Take Off power is limited to 5 mins (or 10 mins with Engine Failure) but climb / cruise power can be set with no time restriction?
Last edited by rudderrudderrat; 17th Jul 2010 at 19:42. Reason: typo & extra text
Jet engine failures in either case are rare, so the specific operational limitation seem to work out...in part 135/121 maintenance is progressive...91 subpart K it is based on a more absolute approach...and they seem to both work
turbine creep is proportional to centrifugal forces and operating temps...and I believe that that factor is the biggest pain regarding turbines
perhaps and A&P or AMT could add based on personal direct observation...of engine conditions
turbine creep is proportional to centrifugal forces and operating temps...and I believe that that factor is the biggest pain regarding turbines
perhaps and A&P or AMT could add based on personal direct observation...of engine conditions
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Well I say that if you lost part of your wing than you would be significantly lighter and be able to stop the aircraft in time. However, who needs a wing to fly..continue on to your destination.
F-15 flying with one wing by an Israeli Pilot - YouTube - Truveo Video Search
F-15 flying with one wing by an Israeli Pilot - YouTube - Truveo Video Search
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Pug - Yeah, it make sense that max takeoff is the norm, regardless of engine hours...if you need it, you need it..and no one is going to tell you that the engine will fall apart if you need max power....the engine is either airworthy or not......and that reduced thrust departures are nice to use, given the conditions, runway, that allow lower fan/turbine speeds, temps to reduce engine wear...curious though that people do reduced thrust departures, then run max cruise power settings all day long...you would think to be consistent with reduced power departures, reduced cruise settings would be pushed as well....hard to believe all the engine wear is in 2 minutes of take off power vs 10 hours of flying basically fire walled at cruise...
But...I am just throwing out there...that by reducing take off thrust...putting your self farther down the runway on purpose...limits runway available to stop....pre or post v1...
So why not just give yourself more options...more runway is nice...if you have the choice, why not take the option that gives you the best chance of a successfull RTO vs feeling pushed to just fly it off, and hope for the best?
Personally I don't see a problem with an RTO..if we can land a plane at 120 kts, we can surely stop one already on the ground doing 110kts...the only question is available runway....
But...I am just throwing out there...that by reducing take off thrust...putting your self farther down the runway on purpose...limits runway available to stop....pre or post v1...
So why not just give yourself more options...more runway is nice...if you have the choice, why not take the option that gives you the best chance of a successfull RTO vs feeling pushed to just fly it off, and hope for the best?
Personally I don't see a problem with an RTO..if we can land a plane at 120 kts, we can surely stop one already on the ground doing 110kts...the only question is available runway....
hen run max cruise power settings all day long...you would think to be consistent with reduced power departures, reduced cruise settings would be pushed as well....hard to believe all the engine wear is in 2 minutes of take off power vs 10 hours of flying basically fire walled at cruise...
Another question, do you land the plane on the last 2,000 or 3,000 feet of runway? And what is the comparative gross weights on take-off versus landing? Hint--Newton's laws apply and cannot be overruled.
Yes, in an extraordinary case not contemplated during certification or training, stopping past V1 may be sensible and a reasonable risk, but that is not how it done in 99.9% of the cases. In the 0.9%, make that 0.09%, cases doing as we train and brief is a far better answer.
This thread, in various forms, has gone on ad nauseum, but Johns I suggest you do several dozen max gross weight take-offs at full power watching the lights at the far end rapidly closing in before baiting an argument on RTO policies. Dust off the overrun a few times.
GF
------------------------Edit------------------------------------
Now, I have re-read page one, I am left wondering John's hatred of reduced power take-offs. What about derates, John? My GLEX has a flex power option in the FMS, so it is not just an airline thing. If you are aware of performance, you know that reduced power may result in somewhat improved controllability near Vmcg (J_T, Mutt, I promise not to mention that V speed again), derates can actually improve runway performance at light gross weights, so there are as many pluses to reduced power as your perceived minuses. Already mentioned, is greatly reduced wear and tear.
Last edited by galaxy flyer; 18th Jul 2010 at 03:44.
Psychophysiological entity
what if a meteorite hits you after V1 or the sky falls after V1...
Ped mode: OFF
Then there was my Naples incident. So, not always true Mr Flyer.
I'd like to think that we might have seen the offending fuel truck prior to reaching V1. After all, he's probably not doing more than 30 mph and we're doing something like 100 kts... you'd have a few distinct clues that you were heading for a collision; prior to V1.
great trailer it was pulling. I went for the next notch of flaps and pulled. Landed again, tidied up the flaps and continued the take off. We never even mentioned it back home. No point, on the list of silly things happening in those days no one would have bothered to read it.
One training skipper, flying with a new captain at Palma, pulled back at what he thought was Vr, and nothing happened. Story goes that they looked at each other, carried on another 10 - 20 kts, and then took off. The training captain went on to a long career in the Ministry of Planes.
well one thing, with the crappy payload/range, especially with the STC'd belted potty seat of most smaller corporate equipment you have to use full power; limiting TO's are more common, if you want to carry any substantial fuel of payload
love the ads for them carries 8 pax 500mn has a range of 1200NM with four occupants
the whole thing deals with cost/benefits and risk/benefits the safety criteria performance criteria, still have to be met...but on the whole how many engine failures are there a critical moments? the Thomson incident made famous by youtube shows that the criteria work..also thrust generally does not just cut out, engines will produces something until they are shut down at the appropriate height. they just produces too much power to use it all all of the time, and it's a real benefit for 'on-condition' engine appliances..but you don't have to use it as there seems to be no such pressure in your operation
also, MCT ,is rarely used in the airlines these days fuel saving depending on the CI analysis, as GF mentioned
LR meteor
oh I forgot
love the ads for them carries 8 pax 500mn has a range of 1200NM with four occupants
the whole thing deals with cost/benefits and risk/benefits the safety criteria performance criteria, still have to be met...but on the whole how many engine failures are there a critical moments? the Thomson incident made famous by youtube shows that the criteria work..also thrust generally does not just cut out, engines will produces something until they are shut down at the appropriate height. they just produces too much power to use it all all of the time, and it's a real benefit for 'on-condition' engine appliances..but you don't have to use it as there seems to be no such pressure in your operation
also, MCT ,is rarely used in the airlines these days fuel saving depending on the CI analysis, as GF mentioned
LR meteor
oh I forgot
Last edited by Pugilistic Animus; 19th Jul 2010 at 02:33.
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Quote "Checking the expected ground speed reading at the 80 knot call is an excellent safety measure. "
Well the problem is that if you got all your static ports blocked then you still would have problems because the ASI shows accurate speed up until you're airborne and start to accent to less pressure.
Well the problem is that if you got all your static ports blocked then you still would have problems because the ASI shows accurate speed up until you're airborne and start to accent to less pressure.
