exceeding POH take-off speed
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In the highlands of Scotland it is regularly 20knts plus with 15 knots gusts. To boot.
In the 1000 hours or so I flew training aircraft PA28,PA38,C172,C152,C150 up there I had never then need to hold the aircraft down and neither did the students I sent solo.
In the 1000 hours or so I flew training aircraft PA28,PA38,C172,C152,C150 up there I had never then need to hold the aircraft down and neither did the students I sent solo.
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Not sure if Johnm is approaching or taking off, but there's never a need to hold a PA28, 38, C150, C172 down after it wants to fly, regardless of xwind (just allow it to fly when it's ready and let it weathercock while maintaining runway heading in the climb).
No wonder there are so many broken noselegs in the AAIB reports! (They generally beak on landing, but mis-use on T/O will weaken them).
No wonder there are so many broken noselegs in the AAIB reports! (They generally beak on landing, but mis-use on T/O will weaken them).
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I'm guessing Mad Jock's wind conditions were not cross wind. Having tried to take off cross wind at normal rotate speeds in those kind of conditions I concluded that a bit faster and airborne cleanly and quickly was safer.
I still do the same in a Trinidad for similar reasons.
I still do the same in a Trinidad for similar reasons.
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I don't disagree with shaggy sheep driver but if the cross wind is gusting it'll try and fly in the gust but won't stay up when the gust drops, the consequences of that can be pretty hairy. Ask me how I know 
Therefore the take off speed needs to have a bit of gust factor.
Therefore the take off speed needs to have a bit of gust factor.
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No john a 10-15knt cross wind is considered normal as well.
I think the strongest wind in the tommy I landed in was 27G39with 15knts of xwind. And the fire boys had to get me in using the engines as a wind break to the tie down area.
You just fly off and set the correct climb attitude and the aircraft does the work for you. Its when you start chasing needles that things get interesting.
Your statement leads me to suspect you have never been taught the correct method of attitude flying.
I think the strongest wind in the tommy I landed in was 27G39with 15knts of xwind. And the fire boys had to get me in using the engines as a wind break to the tie down area.
You just fly off and set the correct climb attitude and the aircraft does the work for you. Its when you start chasing needles that things get interesting.
Your statement leads me to suspect you have never been taught the correct method of attitude flying.
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Mad jock I'm talking cross wind component for take off exceeding 20 kts with 10kt gusts. The worst I've done out of Alderney in a PA 28 was 22 gusting 30 at close to right angles to the runway. I've done 28 gusting 42 in the Trinidad, which has more rudder authority and is heavier.
The poor blighters flying the Trislanders have to give it best much beyond that.
You have to be absolutely certain that when the aircraft leaves the ground it's definitely staying up as you weather cock around 20 degrees as soon as the wheels leave the ground.
The poor blighters flying the Trislanders have to give it best much beyond that.
You have to be absolutely certain that when the aircraft leaves the ground it's definitely staying up as you weather cock around 20 degrees as soon as the wheels leave the ground.
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hold the aircraft down by slight forward pressure and the rotate at about 75 KIAS
The very fact you're having to "hold it down" shows that it is ready to fly, so all you're doing is putting extra stress on the undercarriage which is wasn't really designed to take.
Out of interest, how many oleo seals do you generally get through? Or are you just an occasional hirer so don't see all the extra maintenance work you create?
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I was the sole owner of the PA 28 which never used an oleo seal and I share the Trinidad. There isn't anything savage in holding an aircraft down like this, if it's really ready to fly then off we go, it's all about not letting the aircraft be fooled by a gust, as soon as it's pushing to fly then it flies. I have no desire to control an aircraft on a narrow runway any longer than I need to.
Both POH have a demonstrated cross wind speed which is way below the aircraft's capability.
Both POH have a demonstrated cross wind speed which is way below the aircraft's capability.
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If the conditions are gusty with windshear hold it down as that extra bit of speed will be a good buffer when you are in the air.
Just a crosswind NO.
There are times when especially on bad surfaces ie Grass the aircraft wants to fly and you get launched by a hump.
I can remember being airbourne in a Seneca twin at 65 kts because the bumpy grass runway determined that.
Pace
Just a crosswind NO.
There are times when especially on bad surfaces ie Grass the aircraft wants to fly and you get launched by a hump.
I can remember being airbourne in a Seneca twin at 65 kts because the bumpy grass runway determined that.
Pace
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I know that John but the aircraft will sort itself out at the right attitude. As soon as the wheels come off the deck you get a boost of performance as you get rid of the rolling friction.
the trilander has other advantages over normal aircraft.
this was stolen from another thread.
Britten-Norman BN2 XL
By a well-known ‘Flight magazine’.
Undaunted by technical realities, the design team at Pilatus Britten-Norman has announced plans for the BN2-XL, promising more noise, reduced payload, a lower cruise speed, and increased pilot workload.
We spoke to Mr. Fred Gribble, former British Rail boilermaker, and now Chief Project Engineer. Fred was responsible for developing many original and creative design flaws in the service of his former employer, and will be incorporating these in the new BN2-XL technology under a licensing agreement. Fred reassured BN-2 pilots, however, that all fundamental design flaws of the original model had been retained. Further good news is that the XL version is available as a retrofit.
Among the new measures is that of locking the ailerons in the central position, following airborne and simulator tests which showed that whilst pilots of average strength were able to achieve up to 30 degrees of control wheel deflection, this produced no appreciable variation in the net flight of the aircraft. Thus the removal of costly and unnecessary linkages has been possible, and the rudder has been nominated as the primary directional control. In keeping with this new philosophy, but to retain commonality for crews’ transitioning to the XL, additional resistance to foot pressure has been built in to the rudder pedals to prevent over-controlling in gusty conditions (defined as those in which wind velocity exceeds 3 knots).
An outstanding feature of Islander technology has always been the adaptation of the O-540 engine which, when mounted in any other aircraft in the free world (except the Trislander) is known for its low vibration levels. The Islander adaptations cause it to shake and batter the airframe, gradually crystallise the main spar, desynchronise the accompanying engine, and simulate the sound of fifty skeletons fornicating in an aluminium dustbin. PBN will not disclose the technology they applied in preserving this effect in the XL but Mr. Gribble assures us it will be perpetrated in later models and sees it as a strong selling point. "After all, the Concorde makes a lot of noise" he said, "and look how fast that goes."
However design documents clandestinely recovered from the PBN shredder have solved a question that has puzzled aerodynamicists and pilots for many years, disclosing that it is actually noise which causes the BN2 to fly. The vibration set up by the engines, and amplified by the airframe, in turn causes the air molecules above the wing to oscillate at atomic frequency, reducing their density and creating lift. This can be demonstrated by sudden closure of the throttles, which causes the aircraft to fall from the sky. As a result, lift is proportional to noise, rather than speed, explaining amongst other things the aircraft's remarkable takeoff performance.
In the driver's cab (as Gribble describes it) ergonomic measures will ensure that long-term PBN pilots' deafness does not cause in-flight dozing. Orthopaedic surgeons have designed a cockpit layout and seat to maximise backache, en-route insomnia, chronic irritability, and terminal (post-flight) lethargy. Redesigned "bullworker" elastic aileron cables, now disconnected from the control surfaces, increase pilot workload and fitness. Special noise retention cabin lining is an innovation on the XL, and it is hoped in later models to develop cabin noise to a level which will enable pilots to relate ear-pain directly to engine power, eliminating the need for engine instruments altogether.
We were offered an opportunity to fly the XL at Britten-Norman's development facility, adjacent to the British Rail tearooms at Little Chortling. (The flight was originally to have been conducted at the Pilatus plant but aircraft of BN design are now prohibited from operating in Swiss airspace during avalanche season). For our mission profile, the XL was loaded with coal for a standard 100 N.M. trip with British Rail reserves, carrying one pilot and nine passengers to maximise discomfort. Passenger loading is unchanged, the normal under-wing protrusions inflicting serious lacerations on 71% of boarding passengers, and there was the usual confusion in selecting a door appropriate to the allocated seat. The facility for the clothing of embarking passengers to remove oil slicks from engine cowls during loading has been thoughtfully retained.
Start-up is standard, and taxiing, as in the BN2 is accomplished by brute force. Takeoff calculations called for a 250-decibel power setting, and the rotation force for the (neutral) C of G was calculated at 180 ft/lbs. of backpressure.
Initial warning of an engine failure during takeoff is provided by a reduction in vibration of the flight instrument panel. Complete seizure of one engine is indicated by the momentary illusion that the engines have suddenly and inexplicably become synchronised. Otherwise, identification of the failed engine is achieved by comparing the vibration levels of the windows on either side of the cabin. (Relative passenger pallor has been found to be an unreliable guide on many BN2 routes because of ethnic consideration).
Shortly after takeoff the XL's chief test pilot, Capt. Mike "Muscles" Mulligan demonstrated the extent to which modern aeronautical design has left the BN2 untouched; he simulated pilot incapacitation by slumping forward onto the control column, simultaneously applying full right rudder and bleeding from the ears. The XL, like its predecessor, demonstrated total control rigidity and continued undisturbed. Power was then reduced to 249 decibels for cruise, and we carried out some comparisons of actual flight performance with graph predictions. At 5000 ft and ISA, we achieved a vibration amplitude of 500 CPS and 240 decibels, for a fuel flow of 210 lb/hr, making the BN2-XL the most efficient converter of fuel to noise after the Titan rocket.
Exploring the Constant noise/Variable noise concepts, we found that in a VNE dive, vibration reached its design maximum at 1000 CPS, at which point the limiting factor is the emulsification of human tissue. The catatonic condition of long-term BN2 pilots is attributed to this syndrome, which commences in the cerebral cortex and spreads outwards. We asked Capt. Mulligan what he considered the outstanding features of the XL. He cupped his hand behind his ear and shouted "Whazzat?"
We returned to Britten-Norman convinced that the XL model retains the marque's most memorable features, whilst showing some significant and worthwhile regressions.
PBN are not, however, resting on their laurels. Plans are already advanced for the Trislander XL and noise tunnel testing has commenced. The basis of preliminary design and performance specifications is that lift increases as the square of the noise, and as the principle of acoustic lift is further developed, a later five-engined vertical take-off model is also a possibility."
All in all, a wonderful aeroplane.
the trilander has other advantages over normal aircraft.
this was stolen from another thread.
Britten-Norman BN2 XL
By a well-known ‘Flight magazine’.
Undaunted by technical realities, the design team at Pilatus Britten-Norman has announced plans for the BN2-XL, promising more noise, reduced payload, a lower cruise speed, and increased pilot workload.
We spoke to Mr. Fred Gribble, former British Rail boilermaker, and now Chief Project Engineer. Fred was responsible for developing many original and creative design flaws in the service of his former employer, and will be incorporating these in the new BN2-XL technology under a licensing agreement. Fred reassured BN-2 pilots, however, that all fundamental design flaws of the original model had been retained. Further good news is that the XL version is available as a retrofit.
Among the new measures is that of locking the ailerons in the central position, following airborne and simulator tests which showed that whilst pilots of average strength were able to achieve up to 30 degrees of control wheel deflection, this produced no appreciable variation in the net flight of the aircraft. Thus the removal of costly and unnecessary linkages has been possible, and the rudder has been nominated as the primary directional control. In keeping with this new philosophy, but to retain commonality for crews’ transitioning to the XL, additional resistance to foot pressure has been built in to the rudder pedals to prevent over-controlling in gusty conditions (defined as those in which wind velocity exceeds 3 knots).
An outstanding feature of Islander technology has always been the adaptation of the O-540 engine which, when mounted in any other aircraft in the free world (except the Trislander) is known for its low vibration levels. The Islander adaptations cause it to shake and batter the airframe, gradually crystallise the main spar, desynchronise the accompanying engine, and simulate the sound of fifty skeletons fornicating in an aluminium dustbin. PBN will not disclose the technology they applied in preserving this effect in the XL but Mr. Gribble assures us it will be perpetrated in later models and sees it as a strong selling point. "After all, the Concorde makes a lot of noise" he said, "and look how fast that goes."
However design documents clandestinely recovered from the PBN shredder have solved a question that has puzzled aerodynamicists and pilots for many years, disclosing that it is actually noise which causes the BN2 to fly. The vibration set up by the engines, and amplified by the airframe, in turn causes the air molecules above the wing to oscillate at atomic frequency, reducing their density and creating lift. This can be demonstrated by sudden closure of the throttles, which causes the aircraft to fall from the sky. As a result, lift is proportional to noise, rather than speed, explaining amongst other things the aircraft's remarkable takeoff performance.
In the driver's cab (as Gribble describes it) ergonomic measures will ensure that long-term PBN pilots' deafness does not cause in-flight dozing. Orthopaedic surgeons have designed a cockpit layout and seat to maximise backache, en-route insomnia, chronic irritability, and terminal (post-flight) lethargy. Redesigned "bullworker" elastic aileron cables, now disconnected from the control surfaces, increase pilot workload and fitness. Special noise retention cabin lining is an innovation on the XL, and it is hoped in later models to develop cabin noise to a level which will enable pilots to relate ear-pain directly to engine power, eliminating the need for engine instruments altogether.
We were offered an opportunity to fly the XL at Britten-Norman's development facility, adjacent to the British Rail tearooms at Little Chortling. (The flight was originally to have been conducted at the Pilatus plant but aircraft of BN design are now prohibited from operating in Swiss airspace during avalanche season). For our mission profile, the XL was loaded with coal for a standard 100 N.M. trip with British Rail reserves, carrying one pilot and nine passengers to maximise discomfort. Passenger loading is unchanged, the normal under-wing protrusions inflicting serious lacerations on 71% of boarding passengers, and there was the usual confusion in selecting a door appropriate to the allocated seat. The facility for the clothing of embarking passengers to remove oil slicks from engine cowls during loading has been thoughtfully retained.
Start-up is standard, and taxiing, as in the BN2 is accomplished by brute force. Takeoff calculations called for a 250-decibel power setting, and the rotation force for the (neutral) C of G was calculated at 180 ft/lbs. of backpressure.
Initial warning of an engine failure during takeoff is provided by a reduction in vibration of the flight instrument panel. Complete seizure of one engine is indicated by the momentary illusion that the engines have suddenly and inexplicably become synchronised. Otherwise, identification of the failed engine is achieved by comparing the vibration levels of the windows on either side of the cabin. (Relative passenger pallor has been found to be an unreliable guide on many BN2 routes because of ethnic consideration).
Shortly after takeoff the XL's chief test pilot, Capt. Mike "Muscles" Mulligan demonstrated the extent to which modern aeronautical design has left the BN2 untouched; he simulated pilot incapacitation by slumping forward onto the control column, simultaneously applying full right rudder and bleeding from the ears. The XL, like its predecessor, demonstrated total control rigidity and continued undisturbed. Power was then reduced to 249 decibels for cruise, and we carried out some comparisons of actual flight performance with graph predictions. At 5000 ft and ISA, we achieved a vibration amplitude of 500 CPS and 240 decibels, for a fuel flow of 210 lb/hr, making the BN2-XL the most efficient converter of fuel to noise after the Titan rocket.
Exploring the Constant noise/Variable noise concepts, we found that in a VNE dive, vibration reached its design maximum at 1000 CPS, at which point the limiting factor is the emulsification of human tissue. The catatonic condition of long-term BN2 pilots is attributed to this syndrome, which commences in the cerebral cortex and spreads outwards. We asked Capt. Mulligan what he considered the outstanding features of the XL. He cupped his hand behind his ear and shouted "Whazzat?"
We returned to Britten-Norman convinced that the XL model retains the marque's most memorable features, whilst showing some significant and worthwhile regressions.
PBN are not, however, resting on their laurels. Plans are already advanced for the Trislander XL and noise tunnel testing has commenced. The basis of preliminary design and performance specifications is that lift increases as the square of the noise, and as the principle of acoustic lift is further developed, a later five-engined vertical take-off model is also a possibility."
All in all, a wonderful aeroplane.
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Rereading that rubbish from Boga.
This school it teaching them to do a close in noise abetment procedure as a standard departure.
That is utterly criminal and irresponsible to teach pilots to fly SEP's in that manner.
This school it teaching them to do a close in noise abetment procedure as a standard departure.
That is utterly criminal and irresponsible to teach pilots to fly SEP's in that manner.
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Bluejays
If improving initial climb over an obstacle is your intent, then lifting off at a normal speed and holding it down while accelerating clear of the surface will reduce the drag of the wheels being in contact (particularly on grass), resulting in faster acceleration. Holding it on in a little airplane for more than just a few more kts/mph for a gusty XW is a rookie error.
If improving initial climb over an obstacle is your intent, then lifting off at a normal speed and holding it down while accelerating clear of the surface will reduce the drag of the wheels being in contact (particularly on grass), resulting in faster acceleration. Holding it on in a little airplane for more than just a few more kts/mph for a gusty XW is a rookie error.
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On a fixed single it doesn't make much sense. But on a twin it can. Many twins will start flying below redline, but that's not a good place to be when one fails. Much safer to stay on the ground well above redline or even until blue line and then rotate.
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Oh dear God what a depressing way to start my day.
First I read this gem...
And by the time I got to...
Depression for the state of the training industry had increased to the point I may go to my doctor for anti depression drugs.
How is it possible for any so called school to teach such absolute rubbish to students?
I just came back to reading these forums and sure enough the dumbing down of flight training is progressing downwards at an alarming rate.
How sad to see such garbage.
First I read this gem...
- On hard runway, keep slight forward pressure on steering wheel, maintaining positive nose wheel contact with runway.
On Vr (normally V2-10) rotate aircraft (normally 10 deg nose up).
- Speed V2
- Speed V2
How is it possible for any so called school to teach such absolute rubbish to students?
I just came back to reading these forums and sure enough the dumbing down of flight training is progressing downwards at an alarming rate.
How sad to see such garbage.
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Be careful with that windshear comment, depending on aircraft type that is not a typical windshear recovery technique, most recoveries are executed near the buffet without configuration change or chasing speed but using a constant attitude as much as possible, and yes I realise we are talking about a single piston aircraft.
Could you elaborate on that! Normally in windshear conditions you would add half the gust factor to the reference speed on approach In that situation more than likely you have potential energy from the engine but you also have potential energy available if you have height in the airframe.
In the takeoff early on you have no potential energy available from the airframe and can only dig into the engine which will probably be maxed out on takeoff anyway.
I appreciate holding attitude but we maybe talking about fixed gear flapless takeoffs with a low powered engine.
Pace
BTW.
My earlier reference to 'holding it on' for some a/c so as not to be flying too early for authority, doesn't hurt the nose-wheel at all !
Rans S4 & Aeronca Champ have the third wheel at the proper (rear) end !
mikehallam.
My earlier reference to 'holding it on' for some a/c so as not to be flying too early for authority, doesn't hurt the nose-wheel at all !
Rans S4 & Aeronca Champ have the third wheel at the proper (rear) end !
mikehallam.
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My earlier reference to 'holding it on' for some a/c so as not to be flying too early for authority, doesn't hurt the nose-wheel at all !
Rans S4 & Aeronca Champ have the third wheel at the proper (rear) end !
Rans S4 & Aeronca Champ have the third wheel at the proper (rear) end !
You just fly off and set the correct climb attitude and the aircraft does the work for you. Its when you start chasing needles that things get interesting.