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Flying the Tecnam P92 Echo and Old Wives Tales

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Flying the Tecnam P92 Echo and Old Wives Tales

Old 24th Apr 2021, 15:11
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Flying the Tecnam P92 Echo and Old Wives Tales

Australian Flying magazine May-June 2021, published an article by the editor Steve Hitchen called Echoes of the Future. He described having a dual flight on a Tecnam P92 Echo Mk 2. After Tecnam Australia's Bruce Stark had shown Hitchen around the aircraft at Barwon Heads, Hitchen wrote "Then Stark did something no other aircraft representative has ever done: he threw the keys to me and my instructor-in-crime Murray Gerraty and went and got himself a cup of coffee. Have keys: have aeroplane ...let's fly!

Although the article was comprehensive and entertainingly written I must say my eyebrows were raised on reading the takeoff technique taught by the instructor which appeared to be his personal technique rather than that of the manufacturer. The manufacturer's Flight Manual for the Tecnam P92 Echo publishes, among other items, a Vr (rotation speed) of 41 KIAS [45 KCAS]

In contrast, Hitchen's instructor tells him: "As soon as you power up, raise the nose until the nosewheel is about two inches off the ground and hold it there. Keep her straight with the pedals and she'll fly off the runway sooner than you think. Right. Let's go!
"Hitchen's description follows: "I applied full power and raised the nose; too far apparently and earned a rebuke from the instructor. I eased up on the stick and did a frantic dance on the pedals to keep 1712 within the narrow confines of the sealed section and waited. Soon everything became lighter, and the strip dropped away.."

The Tecnam Flight Manual says nothing about "as soon as you power up raise the nose until the nose wheel is about two inches above the ground and hold it there." That takeoff technique is one of many Old Wives Tales permeating from Australian flying schools that often disregard manufacturer's advice in favour of non-standard personal opinion of the instructor. Excuses offered for this practice vary. Some instructors claim it takes the weight of the nosewheel which is the weakest part of the airframe. Another excuse is it reduces the chances of nosewheel shimmy. Both these excuses are invalid. . Granted, the POH for Cessna singles under Secton 4 Normal Procedures states "Soft or rough field takeoffs are performed with 10 degrees flaps by lifting the airplane off the ground as soon as practical in a slightly tail low attitude." However nowhere in these POH is there mention of taking the weight of the nosewheel during the takeoff roll.

Using the takeoff technique advocated by Hitchen's instructor can lead to immediate loss of nosewheel steering capability; particularly in a crosswind. More problematic is the difficulty in judging two inches of nosewheel clear of the ground as demonstrated when Hitchens was rebuked by his instructor for pulling back too far. The pilot cannot see the nosewheel to confirm the distance from the runway. Another problem is where a wind gust can cause the aircraft, already at a higher angle of attack than optimum due to premature back stick, to become temporarily airborne in a stalled condition. All these problems are solved by lifting off the ground at the recommended airspeed. In the case of the Tecnam P92 that speed is 41 knots.

I recall contacting the Cessna Aircraft Company in USA many years ago and describing the weight off the nosewheel technique commonly used at Australian flying schools on Cessna singles and other similar light types. Their reply was they had never heard of that technique and strongly recommended pilots use the procedures published in the manufacturers POH.

In the late 1940's, flight manuals of many British designed aircraft recommended raising the nose wheel just clear of the ground as the aircraft approached lift-off speed. I understand this was to cater for the significant drag on the nosewheel if slush was present on the runway. The idea being the aircraft was allowed to fly off the ground in its own time rather than have a specific rotation speed. This technique was recommended for the early DH Comet airliner and most other tricycle undercarriage types including the Canberra bomber and Vampire fighter series. In contrast, American designed aircraft rotated at a specific published airspeed. Vampires and the Canberra were exported to the RAAF in those days along with their respective flight manuals.

Indeed, the RAF Pilots Notes for Vampire clearly stated: " Keep straight initially by gentle use of brakes, then, as speed is gained, by coarse use of the rudders. As soon as the aircraft reaches a speed of 60-70 knots IAS, lift the nose wheel just clear of the ground, then at 82-87 knots IAS, ease the aircraft off the ground." Why nose wheels were lifted off the ground at such slow speeds is lost in antiquity but it became SOP for all takeoffs for both civil and military aircraft. This writer flew the early Vampires at RAAF Base Williamtown and Central Flying School where the takeoff technique was to raise the nosewheel around 80 knots and allow the aircraft to fly itself off the ground when it was ready rather than at a specific airspeed. It was an uncomfortable feeling mushing off the ground barely flying.

There were at least two fatal accidents to Comets where the pilot, unable to judge nose attitude over the short nose at night, mistakenly raised the nose too high during the takeoff run. It was also difficult to judge the nose attitude on instruments because of limitations of the design of the artificial horizon. Probably unknown in those days was the significant increase in drag that can form if high nose attitudes are allowed to occur during a takeoff roll. . In both cases the Comets overran the runway because of the failure to accelerate to lift off speed. In the RAF there were similar difficulties with the Vampire.

Closer to home was the overrun accident to a New Zealand civilian registered De Havilland Venom at Ardmore aerodrome on 17 November 1991. That aircraft failed to accelerate during the takeoff run primarily due to the pilot lifting the nosewheel early in the takeoff roll. The resulting high drag caused by the wing being at a too high angle of attack was sufficient to reduce acceleration to a dangerous level. There was also conflicting information in the various flight manuals used by the pilot. See : https://www.taic.org.nz/sites/defaul...nts/91-023.pdf

Finally, my apologies for the somewhat lengthy comment on the Steve Hitchins experience of flying the Tecnam P92 Echo MK 2 for the first time. The intent of this post was to highlight the difference between aircraft manufacturer's advice on how to fly this aircraft and the instructor's personal technique which in turn was passed on to his student. Despite a similar technique (taking the weight off the nosewheel during the takeoff roll) being widely taught at flying schools in Australia and at flying instructor courses, the danger of this technique being inappropriate for an aircraft type for the reasons given above, as well the student carrying this over to other types, is ever present.

It is difficult enough trying to judge how far to lift the nose "to lighten the weight off the nose wheel" as often there is no reliable nose attitude reference especially at night. Far better to stick to the common sense advice published in the manufacturer's flight manual than to listen to Old Wives Tales born of someone's personal opinion from another era.
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Old 24th Apr 2021, 18:03
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I'll bite. As is so often the case, the answer amounts to; it depends. I too was taught the technique when converting a GA licence to RA Aus certificate in a P92 and whilst I can attest that a moderately strong crosswind from the left will convince you to leave the little wheel planted a little longer, in more benign conditions there is merit in the often repeated maxim that a nose wheel is merely there for taxiing and that once on the runway, the aircraft should be operated as God intended ie. as if it had a tailwheel. Couple of reasons. One being that the nosegear is a weak point on the light structures necessitated by aircraft with a MAUW of 544 or 600kg - just ask the various GA schools flying Slings, Foxbats, Tecnams and the like. Secondly, compared to a traditional Cessna or Piper trainer, a P92 is a high performance aircraft, with far lighter and more effective controls, along with a markedly greater power to weight ratio. Even a fairly hamfisted student quickly learns to finesse the attitude to unload the nosewheel and on the grass strip I flew from, the rudder pedals communicated this state pretty effectively. Thirdly, even your legacy Piper/Cessna POH, can be somewhat less authoritative than the scriptures (ask John Deakin) and that goes all the more for less rigorous standards governing LSA.

I quite agree that instructors are far from immune from perpetuating old wives tales ( slipping with flap anyone ), but I'd be wary of automatically dismissing hands on experience in favour of technique by the book only. Besides, whilst I am highly unlikely to experience a low visibility takeoff in a Meteor, I do question the relevance in relation to a day VFR bugsmasher.
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Old 24th Apr 2021, 21:57
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Iíve been living on the edge and raising the nose-wheel for 20 years in all aircraft Iíve flown that will let me do it.

Agreed that in some cases for me a strong crosswind from the left will mean that I need to leave it on the ground. The worst case scenario is a strong left crosswind, on grass on a rough runway, that can be a sticky situation at the best of times in the aircraft that I fly.

With 100% certainty I can say that this technique has saved me from more than one prop strike and a damaged nose wheel.

In some aircraft such as the smaller training Jabiruís, it is highly advantageous to reduce weight on the nose as the nose wheels are somewhat ďsquareĒ and if youíre not 100% flat, the aircraft can ride on the edge of the nose-wheel and spear off the side of the runway, which I have seen students do multiple times with the loss of the aircraft ensuing.

The number of bent and broken nose wheels on the Soar Foxbat and Tecnam fleet is also indicative of the need to be gentle on the nose wheels and to employ techniques to minimise damage.

I agree with your night comments though, you need to be more clinical and operate by the numbers rather than feel. Luckily for many aside perhaps from those operating out of Lilydale, a takeoff at night on a rough grass field is not overly common in the scheme of things, so traditional manufacturer techniques can be employed.

I swear that I have dejavu and that either you or someone else pretty much wrote a very similar post some years ago.
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Old 24th Apr 2021, 22:51
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Zenith Aircraft's 'chief pilot" recommends immediately lifting the nose wheel on the experimental CH701 and CH750 models "and the aircraft will fly right off by itself". However both these STOL aircraft have fixed leading edge slats and we are talking about a five second time window. There are numerous Youtube videos of this Zenith takeoff technique.

BUT, thank you Centaurus for your considered advice. The only time my stall warning is ever triggered is on takeoff - for a fraction of a second after I indeed lift the nose wheel. I never thought of it until now but a gusty left crosswind sounds like a very good reason to hesitate for a second before lifting the nose.
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Old 24th Apr 2021, 23:06
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Not wanting to detract from the thrust of Centaurus' comment, but in case you were interested in the video referenced in the Venom crash report it can be found in the latter stages of this:

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Old 24th Apr 2021, 23:58
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the article was comprehensive and entertainingly written
..and aimed at a particular audience. The general public and recreational pilots.
It's not for graduates of the Empire Test Pilot School.
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Old 25th Apr 2021, 00:08
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FWIW there is another behaviour in nose-wheel pilots I see sometimes. As the aircraft accelerates the pilot relaxes forward on the column and aircraft starts to get light on the mains as the nose pitches down slightly. This because take-off trim is usually slightly nose down at take-off speed.

The pilot keeps glancing at ASI until it gets to the POH rotate speed then will often say "XX kts rotate" then looks up and pulls back very weakly - the nose pitches up slightly and the aircraft is now balanced evenly on all 3 wheels and the speed is indicating 5-10 knots above the quoted rotate speed, the nose wheel starting to vibrate and more runway is disappearing - you can hear and feel the front wheel sigh in relief as it finally gets airborne as they finally pull enough to break contact and the aircraft zooms upwards

I have to admit in response to this I often will suggest the pilot take some weight off the nose as the aircraft picks up speed on the take-off roll, not necessarily to get the nose-wheel up and airborne but to stop the aircraft pushing down on the nose-wheel and avoid a too high take-off speed and subsequent stress on the nose-wheel.

Watching many training aircraft from the side of the runway whilst observing solos, you can see the nose pitch up slightly and the nose wheel oleo extend some way before the nose-wheel actually breaks contact with the tarmac. With the nose pitched up, I think many may believe the wheel is 2" above the runway when it is actually still in contact with the ground.

I do agree, trying to get the nose-wheel airborne as soon as possible is not a great idea and the POH technique is correct however I think there are some subtleties involved in getting pilots to actually do it.

my 2c
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Old 25th Apr 2021, 02:28
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Jonkster, what aircraft would you see that behaviour in (top paragraph), Cessnas perhaps? Just wondering as itís not something Iíve done and am thinking itís a Piper or Cessna thing.
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Old 25th Apr 2021, 02:36
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Training on a low wing Tecnam P.96, (low wing,)04- for nearly 20 years, I always suggested that my students "were kind to the nose-wheel". Never had any problems, but can appreciate some of the comments previously mentioned against the practice are valid
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Old 25th Apr 2021, 03:08
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Originally Posted by Squawk7700 View Post
Jonkster, what aircraft would you see that behaviour in (top paragraph), Cessnas perhaps? Just wondering as itís not something Iíve done and am thinking itís a Piper or Cessna thing.
I have noticed PA28s, 150-172s etc often feel trimmed slightly nose forward for T/O (depends a bit on loading etc). I always assumed this to prevent nose pitch up on T/O.
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Old 25th Apr 2021, 05:05
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This is nothing new, and aerodynamically speaking it has the same effect as pushing on the stick in a taildragger on the takeof roll to ease the tailwheel of the ground.
I both cases (Tecnam and a tailwheel, say a PA18) it gives an incidence to the wings which let them acquire lift as soon as the airflow rises and then the aircraft will take off by itself as soon as it reaches 1,1 Vs. And this eases the strain on the nosewheel of the Tecnam (Or the tailwheel of a Piper), which are both quite flimsy and prone to damage.

However, this technique must be done with a very light touch on the stick, and for any front wheel aircraft it has to be raised just a tiny bit (approx 3 to 5 degrees) of incidence.
Given the low power of a basic trainer, it is essential, and nobody seems to have mentionned it here, just after liftoff the sick must be eased forward to reduce drag and allow the aircraft to accelerate well above 1,1 Vs.

There is a big risk if this is not done to remain in the back side of the power curve or second regime.. And yes it is not advisable in a cross wind, definitely not with a right turn propeller with wind coming from the left, due to torque effects, but both from the left or the right as the cross wind carries a forward component and is often not linear but turbulent and 1,1 Vs liftoff speed does not carry a margin for safety.

Taking off from a grass strip also reduces ground friction drag as you will have one less wheel rolling.

Off topic, I would ad on landing the pleasant sight and finesse of pilots touching down on the mains and holding up the front wheel til lift loss eases it down to the ground like a feather..
An art today lost where aircraft are often slammed to the ground with no control after the flare, plus that nose drift due to uncorrected parallax, that" screech" noise which in addition to not being very elegant imposes torsion. Those old built like tanks Cessna's and Pipers will tolerate that, but today's light and flimsier built aircraft derived from ultralight desing will but if abused will eventually fail.

Last edited by markkal; 25th Apr 2021 at 05:22.
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Old 25th Apr 2021, 05:56
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I swear that I have dejavu and that either you or someone else pretty much wrote a very similar post some years ago
Good guess..
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Old 25th Apr 2021, 06:11
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it gives an incidence to the wings which let them acquire lift as soon as the airflow rises and then the aircraft will take off by itself as soon as it reaches 1,1 Vs


Or, if an unexpected headwind gust of wind happens to be present causing the aircraft to stagger into the air prematurely with stall warning blaring . Not a nice feeling. Aircraft should be flown by the numbers published by the experts, Not by guess and by God. .
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Old 25th Apr 2021, 08:42
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Originally Posted by Tee Emm View Post

Or, if an unexpected headwind gust of wind happens to be present causing the aircraft to stagger into the air prematurely with stall warning blaring . Not a nice feeling. Aircraft should be flown by the numbers published by the experts, Not by guess and by God. .
Sorry to contradict you sir, the Tecnam 2008 we have at the club POH states stalling speed 39 Kts and rotation T.O. speed 44 Kts That is 1,1 Vs
That of course implies as per POH that immediately after liftoff whatever technique used to reach VX or VY nose must be eased forward,
However nobody at the club (but tailwheel pilots) rotates at 40 kts they all wait 55 minimum at that speed you are close to VX, and have enough energy to set climb pitch angle without nose forward transition
It comes to the same, although the first technique gives you the feel and finesse and teaches you the correct reflex to deal with an emergency, i.e.ingrains the immediate response to lower the nose at any hint of speed decay whatever the scenario...

For crosswind and headwind, just hold T.O. run longer by reducÓng angle of attack until reaching corrected rotation speed, as per POH numbers, so no diversion from SOP's

Last edited by markkal; 25th Apr 2021 at 11:34.
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Old 25th Apr 2021, 13:04
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After reading a fair few autobiographies by successful aviators and aviatrices the common recurring theme is to fly the wing (not the nose wheel), this generally only occurs when you quickly get the wing up to speed. Setting the takeoff trim as prescribed by the POH is a good place to start.
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Old 25th Apr 2021, 17:39
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Originally Posted by Centaurus View Post
Good guess..
The uncharitable may suggest that you're trolling then.
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Old 26th Apr 2021, 01:49
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The uncharitable may suggest that you're trolling then.

In Internet slang, a troll is a person who starts flame wars or intentionally upsets people on the Internet. ... Even so, Internet trolling can also be defined as purposefully causing confusion or harm to other users online, for no reason at all.

My comment: Assuming the above meaning of "trolling" is an accurate description of the term, I would suggest there is a slight difference between "purposefully causing confusion or harm to users online" and reasoned argument in terms of aircraft performance regardless of the identity of the author.
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Old 26th Apr 2021, 02:14
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Originally Posted by Centaurus View Post
In Internet slang, a troll is a person who starts flame wars or intentionally upsets people on the Internet. ... Even so, Internet trolling can also be defined as purposefully causing confusion or harm to other users online, for no reason at all.

My comment: Assuming the above meaning of "trolling" is an accurate description of the term, I would suggest there is a slight difference between "purposefully causing confusion or harm to users online" and reasoned argument in terms of aircraft performance regardless of the identity of the author.
I think he just meant that particular comment rather than your first post which was insightful as always
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Old 26th Apr 2021, 08:10
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Judging by the comments so far, it seems the consensus is that early nose wheel lifting is a good thing regardless of the pros and cons. Maybe the majority of readers who elect not to post feel the same. That said, it must be confusing for new students (or even laid-off former airline pilots returning to general aviation) to be told by an occasional instructor to forget the POH, just do as I say and everything will be alright.
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Old 26th Apr 2021, 09:27
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How many flying schools teach takeoff with 10 deg of flap in a 172 these days on a bitumen runway? Iíd tip many. Years of experience tells instructors and pilots about what works well and what is safest. The dinosaur aircraft manufacturers need to get off their butts and update their POHís with the 21 century. Golly, if I climbed my aircraft at the recommended speed, Iíd have cooked 20 engines by now!


For the purposes of this discussion there is a big difference between reducing pressure on the nose-wheel and keeping it 2 inches off the ground.
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