Takeoff Technique For Cessna's

[Mr Garrison]

Just wondering why my training organisation ask us to "Call 40 Knots" as were accelerating down the runway.

What were told is after were clear to take off, we advance throttle fully forward, accerelate down runway maintaining tracking, check airspeed is indicating and rising, check oil temp and pressure, call 40 Knots and then finally rotate at 55KIAS.

I understand all the other checks but not sure why we have to call out "40 Knots".

I will ask my instructor but my only guess is that 40 knots represents approx 2/3's Take Off Safety Speed (TOSS) which is what the theory books talk about with regards to taking off from short runways.

Thanks all....


Mr G

:ok:

[the wizard of auz]

Dunno why they do that.......... I'm usually airborne by the 40 knot mark. ( I love my STOL kit) ;)

[Lasiorhinus]

Is 40 knots reasonably close to your rotate speed?

Myself, when flying things like 172s, I call 50 knots and rotate at 60 knots. I use the preceding call to get myself prepared to rotate. Its sorta like a V1 call, but then in a 172 off the sort of runways I use, theres not going to be a critical speed.

Ask your instructor, she should have a good clear explanation for you.

[The Bunglerat]

FYI, airline SOP's require the pilot to call out at "80kts." Of course, in the case of light aircraft, such a speed would not be relevant, as your typical bugsmasher would already be airborne.

Why the speed check? Airline crews make the call for verification of airspeed readout, and because the speed has a bearing on whether or not the take-off will be rejected under certain conditions. From 80kts up to V1 (consider "V1" as a last-chance decision speed, if you will, on which the take-off can be rejected), there are additional sets of conditions which may warrant a rejected take-off. However, above V1 it's balls to the wall, no matter what - unless you plan on using the fence at the opposite end as an arrester hook.

In the context of your type of operation, the considerations are much the same, albeit in a simplified form:

Recognition of airspeed (the ASI is/is not functioning), i.e. "my aeroplane is accelerating down the runway, thus my airspeed should be registering something by now." If it is, continue. If it's not, "how about I pull the pin before I get up close and personal with the fence at the other end?!" In other words, you don't want to find yourself having used up a good portion of the runway, only to realize you should have been at lift-off speed by now, but the ASI is acting all screwy. Recognition that something is amiss early in the take-off is much better than realizing the same thing after using up most of the available length.

As for the magic number 40, you'll notice your ASI is only calibrated from 40kts upwards (at least as far as I remember from the Cessnas and Pipers I used to fly), hence "40kts!"

Furthermore, it's good airmanship and teaches the right habits for when you do eventually get to fly heavier metal.

[Wheeler]

Some just say 'airspeed alive' - or something. Calling something out will give you an idea of what it 'feels' like. As for this V1, rotate stuff - well, maybe that's the next lesson. My old instructor used to cover up the ASI and the other clocks (Not for take off) but guess what, you find you can get by without an ASI at all in a Cessna. Once you learn what it feels like at certain speeds, attitudes and configurations etc, its amazing what you can do without when you really have to. E.g. Great fun and no problem when you have a total electrical failure - at night.

[swh]

The Bunglerat

FYI, airline SOP's require the pilot to call out at "80kts."

Not all airlines, mainly a Boeing type call, other people call 100 knots.

However, above V1 it's balls to the wall

Ummm, no TOGA is not always selected in the case of an engine failure, derated takeoff setting should give adequate performance under normal circumstances.

Mr Garrison

Ask your CFI, I would also suggest it was adapted from either RAAF or airline two crew procedures and introduced as a good habit as suggest above.

The airspeed call is also used as a pilot incapacitation check in some airlines.

Keep asking questions, its what this forum is for, no such thing as silly questions.

:ok:

[Centaurus]

The manufacturer's POH for the C150, 152, and 172 and no doubt similar types do not mention a check or call of 40 knots during the take off run.

Similarly there is no mention of specific checking of temperatures and pressures in the middle of the take off run. It is just another GA gimmick. Those who think it is yet another GOOD IDEA to foist upon a hapless student these personal theories, should have the courage of their convictions and direct your theories to the aircraft manufacturer with the recommendation that they be incorporated in the POH as a matter of vital flight safety. The replies (if any are received) will be illuminating.

[Lodown]

Very well put. For my 2 Centaurus worth, I fully agree with the last post. A "GA gimmick" sums it up nicely.

[tinpis]

Absolutely..Centaurus.

Another distraction for our hapless tyro when he should be peering out the front anticipating the shove in the back and breathtaking 172 rotation and climb.

[Cloud Cutter]

Yeah, 40 knot call probibly a bit of a waste of time. More appropriate to call 'airspeed active' during a short feild takeoff - and have an abort point. This allows for the possibility of an unexpected tailwind or poor acceleration due to long grass ect.

I also dissagree with checking ts and ps during the roll, too much work for the poor student, and as stated - not required by the flight manual.

As for the 'rotate' speed. In most lighties you don't really need a certain speed, just hold the weight off the nosewheel and somewhere around 40-50 knots raise the nose to climb attitude - the aircraft will get airborne when it wants to. It's not a heavy jet and not designed to be kept on the ground to build up speed.

[J430]

Being a student was only a few years ago for me so I remember well the early days of just about every takeoff there was a new thing to learn. One of the things that I picked up just from observing a really good instructor was when you check ASI, a quick look for Greens on the gauges just to verify you have what you should have, rather than discover it 300' and no runway left that is useful.

After the quick scan its fly by attitude and feel and looking out for traffic or birds (feathered).

I don't know what the heavy metal boys do, but I guess now they have a computer that watches it for them and only flashes up a warning if the need arises!

J:ok:

[Sid Departure]

The "80 kt" call used by airlines (100 kts on some types), is primarily used to check for any discrepancy between the Captain's and FO's airspeed indicators.
If there is a significant difference between the two,(most airlines SOP's state 10 kts) then a rejected T/O should be considered.
As for calling "40 kts" in single engine light aircraft, if it is not part of the aircraft opreating manual then the school teaching this technique should have a very good reason for doing so.
The reasons offered so far do nothing more than add an unnecessary distraction at a critical stage of flight.
A good question all the same Mr Garrison.

Cheers

[haughtney1]

SWH, I dunno what your flying....if I ever lose a hairdryer, the other lever(s) are gonna get bent forward..TOGA be buggered, 5 mins at rated thrust is going to save me and my passengers..:ok:

Just to say that there is more than one way to skin a cat, but strictly speaking all transport catagory aircraft are performance limited by their ability to fly away with a V1 critical power unit loss, hence TOGA is the promulgated thrust setting :cool:

[Tinstaafl]

...and if you're using a reduced thrust t/o to increase MTOW by reducing a V1min limit caused by Vmc? Are you sure you want to go balls-to-the-wall then...?

[Chimbu chuckles]

but strictly speaking all transport catagory aircraft are performance limited by their ability to fly away with a V1 critical power unit loss, hence TOGA is the promulgated thrust setting

Wrong.

As to '40 kts'? If it's anymore than a way of signifying to the instructor that you have checked airspeed alive then it is, as mooted by others, a crock of ****e that stinketh.

Would I stop on a short, wet runway for no IAS in a lighty?

No...but then I was taught how to fly without one if the nead arrises.

There seems to be a lot of good usefull stuff that is not taught these days in primary flight training...and it seems, at times, it has been replaced with rubbish aped from 'the airlines'. Invariably the instructor has never been in an airline and actually has little idea of what he speaks but has read it somewhere.

[franksnbeans]

Just in regards to the "80 knots" call commonly heard in the bigger types, I believe I read somewhere that the performance charts for TO are based on TO power being set by 80kts. If it is not set by that stage, you risk cleaning up the fence.

Would probably be an ideal time to cross check/verfiy that both the capts. and FOs speed tape are both reading the same thing.

Just my 2 cents worth!
fnb

[Ultralights]

In a C182, i dont see a need to call 40, but i do check to see if the indicator is working, on more than 1 occasion, just because the ASI is working and climbing as you accelerate down the strip doesnt mean it HASNT failed. on 2 occasions in a piper Arrow, accelerating down 11R at YSBK, the airspeed worked fine (so i thought) rotated at 65, accelerated to 80, gear up. accelerated through 90, but heres where things went pearshaped, attitude OK, yet the ASI continued through 120Kts, then 140, through yellow and continued through 3 complete circles of the dial only to settle a few degrees before 0. a circuit was completed followed by a normal landing.

fortunatly my instructor, Brian wetless regulalry stuck bits of carboard over instruments.

ask your instructor if he/she can do some partial panel work with you.

[haughtney1]

Mayby some clarification here....

Tin......why would reducing t/o thrust increase M/tow...by reducing V1?..surely you reduce V1 to balance a shorter field.

V1 is a decision speed to fly, and therefore cannot be less than Vmc(a), V1 is calculated (in the company I work for) based on field length/slope, optimum flap setting, regulated & actual take off mass, temperature, and pressure altitude, VMC is always less than V1 in these calculations.

Chimbu...explain where and why Im wrong, I was refering to JAR Ops jet transports rather than T/Props.

:)

Personally I think an airspeed alive check is sufficient in light a/c..most will tell you when they are gonna fly.

[donpizmeov]

Haughtney1,

If you use assumed Temperature to reduce your take-off thrust, you are correct. However, if as swh and tinnie stated you use the derate, you are wrong.
In essense assumed temp considers the same engine performance but on a hotter day. The derate, treats the engine as being a totally new one at reduced thrust. So the VMC and V1 when using a derate is calculated at the reduced thrust. So, if you were to push all the levers forward after a failure as you stated, things may well go askew. The derate is not an option on smaller jets I guess.
Also of note, there is really no requirement to push everything up even when using the assumed temp method, as takeoff perf has been done at the reduced thrust. On a larger and bigger thrusted airplane, it is sometimes better just to leave the levers where they are as performance is not limiting when they are light, but the foot work might be. However when you are hot and heavy, the assumed temp and the outside temp will probably be close so the little extra thrust might be helpful.

Don

[swh]

haughtney1,

Looking at your profile, I assume your a 757 F/O.

As Tinstaafl eluded to, reduce the rated thrust value and you can get a lower Vmcg-limited V1. If the rated thrust is reduced the Vmcg and Vmcg-limited V1 reduce, which means V1 can reduce, or an increase in MTOW to keep the same ASDR.

Reducing rated thrust, FLEX, assumed temperature are all about the same thing, not using all the performance available from the engine to extend service life, while assuring adequate climb performance. Selecting TOGA is not always necessary for all types, however it is always a consideration.

If you remember you B200, it even had derated engines.

:ok:

[haughtney1]

Swh, don, I agree with all thats been said, the company I work for base V1 on an optimum flap setting that is arrived at using an assumed A/c Mass, pressure alt, OAT, and TORA(JAA..Take off run available). All things being equal V1 must always be greater than or equal to VMCA..or else we(who I work for) are operating illegally (outside our Ops manual spec.
I also thought VMCG was a function of A/C mass therefore it should be higher than V1 in any case.

I guess my point is that I prefer to use the excess thrust if I need it:ok:

Oh and ya gotta love the Kingair!..PT6 heaven

:)

[bloggs2]

haughtney1,

mate might be time to put the golf clubs down and pick up some of those old perf manuals floating around the place. Can't fault you for trying to help some one out, but this stuff can be confusing enough anyway without adding to it.

I also thought VMCG was a function of A/C mass therefore it should be higher than V1 in any case.

As i understand it (and i am no expert) the position of the mass in relation to the rudder, not the mass itself, is the thing with Vmcg, and Vmcg is always less than V1. Pretty hard to catch the schwiing if Vmcg is greater than your V1.

I guess my point is that I prefer to use the excess thrust if I need it

Until it flips you on your back cause you have run out of boot and it kills you. You may not always be allowed/able to use this excess thrust, as alluded to in previous posts. It depends on how you crunched the numbers to get airborne in the first place.

Back to the original thread,

We use 80kts as an incapacity check to make sure the old fart next to us hasn't carked it, otherwise you may be checking out haughtney1 on the 10th tee shortly after calling V1 rotate. Most glass types will flag an airspeed disagree pretty quickly (5 kt diff for > 5 secs on our type). Which gives plenty of time as it takes about 15 secs to get to 80kias. Fark nose why you would call 40 kts in a vfr bugsmasha, they fly fine as chuck said without it. Most people will only kill themselves when they notice it missing, but flew fine up until then.

[haughtney1]

Well done Bloggs..you passed the test..:( quick question....if VMCG(ground) is less than V1..what happens when you lose an engine above VMCG and below V1?

And your referring to VMCA(airborne) when you talk about lacking rudder authority..which incidentally should be less than V1, and less than or equal to VMCG at MTOM. which is why transport catagory a/c are performance limited on this basis i.e. it is well understood and hence the numbers are crunched in that fashion. Orrrr else the plane in question could never be certificated and operated as a public transport a/c.
Unlike many light piston and T/P twins.

I agree can be confusing...but thats my understanding.



:ok:

P.S. I need all the practise I can :\

[bloggs2]

haughtney1,
if VMCG(ground) is less than V1..what happens when you lose an engine above VMCG and below V1?
as you yourself would have briefed hundreds of times, you close the thrust levers, disconnect the autothrottle, make sure the speed brakes have deployed, select reverse on the good engine and let the autobrake bring you to a halt (or max manual braking as required) maintaining the centre line. Vmcg is always less than(or at most equal to) V1, as once you are above Vmcg you can control the aircraft directionally with the rudder alone (have another look at the definition, i think you have it arse about). Prior to V1 you are interested in Vmcg as you aren't (technically anyway) going to get airborne, at or above V1 you will take it into the air, and then you want Vmca to be less than Vr.

What i am refering to, as did donpizmeov and others, is the case when you derate (say you have a 26k engine and you derate and use performance for a 20k, this is different to an assumed temp thrust reduction). Then if you have a problem AT OR ABOVE V1, you continue and if you were to advance the thrust levers past the 20k TOGA bug and beyond, to the 26k thrust limit (firewall) you are going to start to have directional problems as the thrust you are introducing is inexcess of what you used to calculate your takeoff performance figures for that weight. As others have said it is not necessary as you have adequate thrust even at the calculated setting, or if in doubt about terrain clearance, the TOGA thrust for the calculated derate, not full welly. Have another look at the previous posts, they explain it better than me anyway.

Not having a go at you here, as this stuff does slip from the memory if you don't keep looking at it and i am certainly no expert. (as others may point out when they read the above, which i hope is correct) :ok:

[haughtney1]

Actually I do have it face about arse:p (stems from me mistakenly thinking that VMCG included aerodynamic controls)

oh dear........haha...hey at least you were nice about it:ok:
and whats with these baby 26K engines??


:p goin back under my rock.

The really sad thing is..thinking about this in my bloody sleep!

[bloggs2]

No prob. Know what you mean about thinking about things like this when you should be sleeping.
whats with these baby 26K engines??
We do the best with what we have :{

[7gcbc]

Close my eyes, Open the throttle and I just hold everything "just so" and when the bumps and rumbles stop and it gets smooth , I open my eyes!

works every time :D

compliment to Bloggs for a gentle and erudite explaination, and not the typical stepping on toes, nice post , not that I understand a word of it however.........

[atyourcervix73]

Haughtney....you plonker:p stick to combing your hair!!!

Bloggs2, dont mind H, he was an abused child:}

[haughtney1]

Heyyyy....I resemble that remark, I'm calling my Dad:p

[bloggs2]

7gcbc,
not the typical stepping on toes
thanks, wouldn't do it on the flight deck, why do it here. Best result all round if you can learn something, and i might have too if i didn't have it right.

atyourcervix73,
i didn't, after all its not easy being a kiwi. :rolleyes: (don't mention the rugby) :ugh:

[tinpis]

Har har Chuck... the good old days we had a nervous quick glance at the ASI to see if it was flickering just before falling off the end of a PNG strip.

[Chimbu chuckles]

and then poled forward to avoid whacking the end of said strip with tail of said aeroplane...IAS? Merely of academic interest...and not that many of us were academics;) :ok: :E :ooh:

And no kiddies...we're not joking:uhoh: :{

[Pinky the pilot]

Tinpis and Chuckles; Interesting that you gentlemen should mention the subject of those PNG strips..:E
Only once did I ever do what you described in your previous posts on this page.;) T'was at Kamulai or Sopu, can't remember now but I was even sufficiently possessed by whatever demon to yell "Banzai" at the top of my voice as we shot off the edge of the strip!!
Caused a severe sense of humour failure amongst some of my pax as well!!
And I would'nt have changed anything for quids!!!:ok: :ok:

You only live twice. Once when
you're born. Once when
you've looked death in the face.

[Chimbu chuckles]

Sometimes, as I get older and marginally smarter, I wish I could only remember doing it once:D

Tinny do you remember/was it built in your day a strip called Nomane. Just east along the Wahgi from Diriman. Heading east from Diriman it was actually the second strip on the right...From Goroka straight through the kaw Kaw Gap, across the eastern end of Mt Elambari and on the south side of the Wara Wahgi?

350m long, 19m wide, the first 100 or so reasonably flat (maybe 3%) and then around a 20 degree corner and then up to about 15% with a transverse slope of around 5% and a deep barret either side of the strip. Typical of PNG the side slope was reverse camber.

It was a RLA up to 87 and then, along with all the god squad Restricted Landing Areas, it was derestricted and open slather for us heathens.

100m in on the right was a bridge over the barret into the parking bay just wide enough for the wheel track of a Twotter..maybe...not sure I ever actually saw a Twotter there, maybe once...usually just me in a C185/Islander and sundry god squad in their Turbo 206s.

Terrible windy place from late morning....strong quartering tailwind from the right on takeoff...given that you had to turn left during the takeoff roll and the strips transverse slope was down to the right the wind sorta didn't help much. Threshold elevated about 2000' above a gorge. Elevation about 6000' up a 9000' ridge....BIG descending air on short finals!!!

Remember dat one?:ooh:

Cannot say as I remember ever looking at the IAS on takeoff there...especially the time I started my takeoff roll from abeam the parking bay in Clyde Cessna's finest. :E

[Centaurus]

Cloud Cutter. You wrote:

As for the 'rotate' speed. In most lighties you don't really need a certain speed, just hold the weight off the nosewheel and somewhere around 40-50 knots raise the nose to climb attitude - the aircraft will get airborne when it wants to. It's not a heavy jet and not designed to be kept on the ground to build up speed

In "most" manufacturer's POH there is no mention of "holding the weight off the nosewheel". It is yet another GA myth (there are lots of them).

If you are taking off from a rough or soft field the C152 /C172 POH does state that the aircraft should be lifted off the ground in a slightly tail low attitude. On a normal take-off the POH states that at 50 knots IAS, lift the nosewheel. This of course is the actual lift off speed listed in the Takeoff Distance Chart. It has nothing to do with the commonly held GA myth of "taking the weight off the nosewheel." The latter may lengthen the take off run due to extra drag and thus invalidate the take off performance chart.

You also mention that "in most lighties you don't need a certain speed....it will just get airborne when it wants to".

There are at least 150 different "lighties". Do you apply your own general fits all take off technique for each type you fly - thus ignoring the manufacturer's POH recommenadtion for each type?

For normal takeoffs, the Cessna POH's state a specific airspeed to lift off in order to meet the takeoff certification performance requirements. Believe me, some of these GA myths are very convincing - particularly if your instructor has hammered them into you as God's Own Truth. Best stick to the speeds and advice in the manufacturer's POH. Saves you grief with the lawyers if you stuff up and bust the aeroplane one day.

[Chimbu chuckles]

Centaurus.

Some of the 'myths' are indeed enfuriating but not all are rubbish. The 'holding' the weight off the nosewheel' one is a soft/rough field technique which is very valid. Particularly soft fields...I well remember doing a first landing at a newly 'finished' strip in PNG in order to declare it open. My usual mount was a C185 but it was in for a service so I went in a Turbo 206...lots of grunt me thinks..no worries. I very nearly didn't get airborne because of the nosewheel dragging through soft areas in the surface...and then I remembered holding the nosewheel off and managed to get airborne...the next day in the C185 (taildragger) was a doddle by comparison.

As to holding the weight off on long hard runways...or even shorter smooth runways and then rotating 'a little more' when approaching flying speed a letting the aircraft fly when it's ready?

Well why not?

I would suggest the little extra drag from a slightly deflected elevator is not significantly more than the drag from a nosewheel bearing a significant weight.

The ONLY single engined Cessna type I have not flown (built post 1960) is the C208 Caravan. The above technique works well in every one. In the 180/185 series raising the tailwheel a little a letting it fly off worked too...wonderfully.

I have flown just about every piper single...ditto.

It works well in my Bonanza.

These are not FAR 25 certified aircraft and the performance graphs in the POH are all very interesting but, in my opinion, are not to be used to decide exact speeds and Tkoff/landing distances with a sharp pencil and then flown like you did in a 737.

What did you do in Tiger Moths when you learned. What about the Harvard and Mustang...I have flown the first a fair bit, the second a few times and I'd bet the Mustang was the same...raise the tailwheel a bit and away ya go....they fly when they are ready.

[AlbyMangels]

I reckon its a High Wank Factor myself.....;)

[Lodown]

I concur with Chimbu on that one Centaurus. Tried it several times in various aircraft in an unofficial capacity in my much younger days...leaving the nosewheel down and taking the weight off. Shorter take-off distance every time with the nosewheel off, and leaving it down on a strip with grass any longer than the centre of the MCG is almost dangerous. On a gravel strip, it helps get the prop that little further away from the stones and ruts have less impact. Doesn't make a great deal of difference on a sealed runway, but it still seems better than letting the nosewheel shimmy and shake.

[tinpis]

No that was after my time Chuck.
I did go into a few of the god botherers strips in the Sepik.
And some pretty ****e awful excuses in the Markham and Kuka kuka country but that was in the lovely Turbo-Porter which didnt need an ASI :}
Once landed and got bogged in a 402 got everyone off and pushing.
After slowly moving down the strip got the nose off and away I went leaving some very mud be-splattered SLF to be picked up a couple of days later :p

Cant remember the name of the strip ..up the coast from Madang with a active volcano just offshore and a Betty bomber in the parking bay?

oh..oh..was it Awar?

[Cloud Cutter]

Centaurus

Sometime you have to use the old noggin and realise that the POH for these types of aircraft take a very simplistic view of what is invariably not a simple exercise.

When I was instructing, the only thing I drummed into my students was that you can't write a manual to cover every possible variable, and discretion is wise.

[Centaurus]

Sorry all - I didn't mean to be over-pedantic. Of course, with rough surface, long grass fields you get airborne with as short a take off roll as practicable. Hence the Cessna singles POH advice of "lifting off in a tail-low attitude". And that in turn means holding the nosewheel clear of the ground and letting the aircraft fly off. The flip side is that too much nosewheel high and induced drag on the wings cuts in and bang goes your reduced take off run and you might even have a wing tip stall if you stagger off at too low airspeed. The Cherokee Six accidents mentioned in the old Aviation safety Digets are worth studying in this regard.

Truth to tell then, is that for a normal take off on your typical Bankstown, Jandakot, Canberra, Archerfield, Moorabbin, Parafield and Essendon (and Point Cook) hard surfaced runways (and a thousand like them) where the majority of people learn to fly, there is no requirement to "take the weight" off the nosewheel until you reach the recommended published speed in the POH and you pull back on the stick to get airborne and in the process you are taking the weight off the nosewheel so beloved by so many.

If as does happen with poorly maintained nosewheel trainers, you experience nosewheel shimmy as you approach lift off, then it is a defect and it should be entered into the MR asap before the next pilot cops it and maybe damage engine mounts.

The danger of letting the aircraft fly off "when it is ready" is that with the slightest wind gradient or gust, the aircraft may waffle into the air prematurely and then you are stuck in ground-effect while you try and accelerate out of the slow speed state.

Years back there were a host of crashes in Vampire jets because pilots were taught (it was in the Pilot's Notes) to lift the nosewheel at 80 knots and run along on the main wheels until it got enough lift (read angle of attack) to fly off. Pilots Notes Vampire Mk F1 at page 20 stated: As soon as the aircraft reaches a speed of 60-70 knots IAS, lift the nosewheel just clear of the ground then at 82-87 knots ease the aircraft off the ground".

There were spectacular crashes when the pilots (especially on night take offs) lifted the nosewheel too much and the Vampire would scarp along in a high drag state with lack of acceleration until you either ran out of space or you dropped the nosewheel a bit to accelerate.

The Venom crash in New Zealand a few years ago wrote off a perfectly good aircraft when the pilot aborted late after failing to accelerate due too high nose attitude during the take off run. The early Comet airliners had similar problems because it was not possible to judge exactly how far to lift the nosewheel during the take off run. The British aircraft like the Vampire and Comet did not have a VR as such. The worry was slush build up in front of the nosewheel in winter and that is why the general rule was to lift the nosewheel clear of the ground on all take offs.

I don't really give a stuff how people fly Cessna's today, but it gets up my nose hairs a bit when the recommendations of the manufacturer are cast aside in favour of a "general" technique for all types. Simply put, the weight off the nosewheel teaching at flying schools is perpetuating a myth.

I wish I had it here, but years ago I wrote to Cessna in Wichita (?) about this Australian weight off the nosewheel theory, and the reply was that Cessna had never heard about it and that the method recommended in the POH was the only technique certified. The tail-low technique was, however, recommended for soft or rough field surfaces.

And by the way, I once asked a grade 3 instructor how he actually taught his students how much back pressure was needed to take the weight off the nosewheel. He said he that if you pulled back the control column early in the take off roll, until you could see the hole in the control column shaft where the gust lock pin fits in, that is the way to get the weight off the nosewheel. He actually taught his students to look down for the hole during the take off run. I thought he was having a lend - but that is what he had been taught on his instructors course. I leave that gem with you.

[Chimbu chuckles]

There was a crash at LAX many moons ago when a F86 being flown by an inexperienced (on type) pilot scorched off the end and smashed into a ice cream stand killing many innocent bystanders...it almost ended warbird operations and heralded the introduction of a formal endorsment process and standards...it was the same thing...over rotated on takeoff and not enough thrust at low speeds in early jets to overcome the induced drag.

But Cessnas are NOT 1950s technology fighters.

The correct technique, on long hard runways, is to begin the takeoff roll with VERY slight back pressure and as the nose wheel starts to fly just let it skim a few inches above the runway...as you approach flying speed (you can feel it in your seat) ease back a little further and let her fly off...and then let her accelerate and climb away at a reasonable speed.

As for using a hole in the pole :ugh: if that is not a classic example of the lack of 'feeling' in (way too many) young pilots I don't know what is.

Charging down the runway until some artifical Vr is reached and then 'rotating' to a high nose attitude and climbing away at Vy/Vx is just aping 'airline flying'. It is bad technique in the class of aeroplane we are discussing.

Light aircraft are not airliners and should never be flown as if they are.

[gaunty]

Chuckles me old :ok:

Hmm yes and no.

Yes, if you delay rotation beyond the recommended, the centre of pressure keeps moving aft and increases the amount of elevator required therefore more drag even unto not having enough elevator authority to get the nose up, especially if you have a forward C of G, as you trundle off into the fence like unto a wheelbarrow.
and;
No, too early and you are by virtue of creating lift also creating that dreaded induced drag even unto off or close to the back of that cursed curve.

Either way you are using much more runway than you really need.

IMHO same old same old for airliners even as for them Cessnas or any lighty, different energy equations maybe but the lift/drag/power relativities remain the same.

Mr Cessna suggests in his recommendations O or min A of A for min drag/max acceleration up to the point where it's time to go then gently rotate.

I am sure you'll agree on limiting runways you gotta fly the numbers and technique is critical.

Most people I see TO and Land way too fast as if a bit of extra speed gives em a bit of extra buffer and then crz at 60% (or some other guru or aero club setting :rolleyes:) to "save the engine" and wonder why they dont get book TAS, wallowing along on the back of the curve using more fuel than they should and actually labouring the engine something chronic. Sorta like fifth gear up a steep hill:{

Centaurus mentions "shimmy". Might I suggest that he's right and the reason there's a lot of this nose wheel lifting about taught, is for no other reason but to stop the shimmies brought about by lack of or poor maintenance. If you've never seen a ship shimmy itself to bits you haven't lived, i.e. if you dont die laughing.:p

As for his Grade 3 friend, sound like the Prince of Wales routine lives still.:{

[Taildragger]

Some time ago, I read an article in a GASIL, UK safety publication, by a CAA Gent who recommended that if the ASI was not alive, then the T/O should be discontinued Even if this means overunning the strip !! I was (And still am) aghast at this advice, and checked around opinions in the Dero Club one evening. (Including Chimbu) who repeated his Crock of ****e that stinketh opinion) I tracked the said CAA gent down and had a fairly long discussion with him as to the Wisdom of his advice. I agree with the discontinue T/O bit, but surely never if it meant an overun. In PNG particularly, where the overun surface could be rocks, or even a steep cliff, it would most likely take off the gear legs and puncture the tanks. Good recipe for fire that, not to mention puncturing the crew/passenger compartment. . Any low hour pilot has been taught to handle the aircraft on limited panel (It is in the syllabus) and should be able to operate the aircraft back to a safe landing by feel...maybe a bit fast though.
I have done it on two occasions on departute from and had no significant problems. I repeat....I don't recommend it, but it is far far better than an overun and possible breakup.
The said CAA Gent and I parted company agreeing to differ at the end of the day, at least I did....he was convinved of the rightness of his advice. Any opinions.

[Cloud Cutter]

I agree with you 100%. Flying a light aircraft without an ASI (or other flight instrument) in VMC should cause minimal drama. Certainly not worth a late abort.

The airspeed active check I was refering to is for a short field takeoff and is to ensure expected acceleration (with reference to the airmass) is achieved by a very early abort point - aborting from this point should cause no problems.

[pall]

Flying Cessnas I have found light back pressure on elevator results in the nose wheel easing off slightly before the AC wants to fly.

I was taught this was the accepted method of take off for this type.

Flying Pipers, they seem to just sit on the strip solidly throughout the take off roll with little chance of the nose wheel lifting. In fact they seem to need a hefty deliberate yank to rotate after the required speed has been reached.

[Sexual Chocolate]

Right on, taildragger. First job I ever had was flying a 182 which had one of those home made, airsped activated metal tabs that save you the trouble of having to take the pitot cover off at the start of the day and put it back on at the end of the day (convenience!). Don't know exactly what it was but got a wierd airflow happening just as I rotated and the ASI started jumping round all over the place. Never got trained on how to deal with this one, freaked me out a bit when I first saw it - but for the life of me I can't think what the big deal is? Fly your standard power settings and attitudes, keep the speeds up if it makes you nervous, land flapless if you're worried about busting flap limits and bring her round for a normal circuit..... Might get your heart rate up if you're a little green when it happens and you haven't been trained to deal with it, but risking gear damage or worse? Reckon boys like that might do well to stay on the ground if they're so attached to it.....

[Chimbu chuckles]

Gaunty me old:ok:

As pall suggests...a Cessna flys off with little or no effort and a Piper takes a little more...particularly the ones with the dumbass T tails.

I flew taildragger's taildragger (C180) last week in the UK...raise the tailwheel a little and let her fly off. 99.9% of Cessna pilots WILL NEVER SEE an airstrip where the above does not work perfectly....as for induced drag and moving centers of pressure?:rolleyes: :yuk: We are talking Cessnas not F86/Vampire/Meteors.

[Capt. On Heat]

Only need two things to fly a light aircraft-oil pressure gauge and a clock.

[the wizard of auz]

while we're on the subject of being pedantic,
you might even have a wing tip stall if you stagger off at too low airspeed.
I thought stalling was a AoA problem........now, if a wing was held at a constant AoA and excelerated from a standstill, wouldn't it already be stalled, and then unstall further along the takeoff roll?. why would it then stall again if the AoA is still the same as it was when the take off roll started?. why would we then have a wingtip stall?. isnt that why wings have washout designed into them?, to stall the wingroot first?. so the ailerons are still effective right up until the whole wing is stalled?.
Just being the devils advocate here. :}

[barit1]

Chuckles said:

There was a crash at LAX many moons ago

It was Sacramento, late 60s/early 70s, and it was a Canadair Sabre. Otherwise - as you said.

My father instructed in AT-6 Texans during WWII - and he said the ASI in the front panel was blocked off below 100 mph to get the student used to flying by feel and attitude. I'm not so sure that was the wisest part of their curriculum, but it did have some advantages. Twenty years later he had a blocked pitot in a similar category airplane and had no difficulty flying or landing it.

By contrast, I have heard of a PPL waiting. waiting, waiting for Vr to appear on his PA-28 - and ran right off the end into a fence.

[Chimbu chuckles]

Capt, On heat....what is the clock for?:ok:

[Capt. On Heat]

CC To see how long you've got till you run out of fuel!

[GOATRIDER]

try applying full aileron into wind- as soon as that wing lifts the aircraft will fly...I use this method all the time in 185s and 206s for remote strip work...try it and see...

[tinpis]

Which aileron do I use in a tailwind?:hmm:

[the wizard of auz]

The big one on the back. Sheesh tinny, don't you know nuffin?

[GOATRIDER]

still apply the same technique tinny----better still on remote strips try not to use a tailwind...and remember tinny- theres no substitute for cubic inches...

[Lead Balloon]

I've been taught that to take off on a soft field you keep the nose up for all of the take-off (yoke in lap from start, letting go gradually as airspeed increases), until you get to 40 KIAS and then pull the aeroplane off the ground - level it out so that you experience ground effect then wait until it accelarates to 67 KIAS until you commence a normal climb. Ahhh yes... and 10deg of flap which you get rid of once you're at 67KIAS.

Pretty funny screwing it up the first time with sparks flying with the grinding of the empanage tie down. Also kind-of weird to use peripheral vision only to stay on the runway.

[tinpis]

Pretty funny screwing it up the first time with sparks flying with the grinding of the empanage tie down.

Soft surface?

[Lead Balloon]

No the first time I practiced was on hard surface. The school wouldn't allow the aeroplanes to be used on soft. Wasn't covered by the insurance.

[tinpis]

The school wouldn't allow the aeroplanes to be used on soft. Wasn't covered by the insurance.


:hmm:

[Lead Balloon]

Unlike Australia Tinpis - most every airport is sealed in the States. So you may scoff, young man, but it is true.

[GOATRIDER]

yeah thats right- and most runways over there are 13000ft long...what do you call a small strip 10000ft?...I guess its like your movies too- The only country in the world that can squel their wheels on gravel...IM WITH TINNY ON THIS ONE

[Pinky the pilot]

so you may scoff young man...
Tinpis......young???????? Er...well......ok......:D :E

You only live twice. Once when
you're born. Once when
you've looked death in the face.

[Chimbu chuckles]

LB Tinny was flying Cessnas out of muddy strips in PNG quite probably before you were born :ok:

[Lead Balloon]

On the face of it - it does look stupid. I'll grant you that.

But it is stipulated in the charter agreement. Which is OK for Phoenix due to the high number of sealed airports. I have seen that places like Montana are well endowed with grass and dirt strips and I would assume the flying schools wouldn't have the luxury of mandating this rule, and I would assume that they would spend a little more on maintenance as well.

As to mr Pis and his age... with the age difference described one can only wonder how he gets that walking frame in the cockpit.

[185skywagon]

try applying full aileron into wind- as soon as that wing lifts the aircraft will fly...I use this method all the time in 185s and 206s for remote strip work...try it and see...

re 185's: If the tail will come up, it will fly.

[cessna 152 pilot]

Flying A cessna 152 is simple especially for the take off.

Apply full into wind aileron relaxing as you go

Keep it straight on the runway

at 40 knots relax the pressure on the nose wheel (pull back)

at 54 knots lift off

[barit1]

Refresh my memory - I flew 150's a long time ago, but never a 152. Max angle of climb (obstacle clearance) was probably 50 kts?

[Chimbu chuckles]

cessna 152 pilot please go back and read the whole thread again.

[Back Seat Driver]

Barit 1 My C152 POH says Max Angle =55 Kts
-In regard to the original post about calling "40Knots" I have no idea - not taught at my school. - however C152 'Stall Speed CLEAN = 40 kts' maybe that has some bearing on it, but I don't beileve teaching youngsters heavy metal ops theory is a good thing. Teach them to fly a 152 or whatever. Better to leave airline training to the airline training captains. Horses for courses..
And as 'c152 pilot' says taking some weight off the nosewheel at 40 is in some ways similar to the original question, he may not call '40' but he is checking the ASI to see when to act.

[A37575]

Full aileron into wind for take off? What rubbish is that. Unless the crosswind is near max limit then no aileron needed and even at max crosswind, just a smidgin to keep the wings level.

[cessna 152 pilot]

A37575,

What you say is true. You only have to apply full aileron when the crosswind is near the maximum. If you are flying a C152 the maximum crosswind is only 15knots.

Where i fly there is only one runway and 9 out of 10 times we have a 15 + knot crosswind.

Makes it great fun for the newbies when they do their first circuit lesson.

[Cloud Cutter]

It is a good idea with any reasonable degree of crosswind to start with full aileron and slowly wind it of as the airspeed increases. The reasons for this are twofold - there's the obvious protection against a gust of wind lifting the windward wing, but also the often overlooked factor of using aileron drag (adverse yaw) to help keep straight. With anything more than about 10 knots across I always start the takeoff roll with full aileron deflection, reducing at rotate to just about neutral as I neutralise the rudder.

You quite simply will NOT manage the same maximum crosswind with no use of aileron.

LB - I don't think it would be advisable to use that rather extreme technique on a soft surface. To use it on a hard surface is just plain backwards.

[Capt. On Heat]

The only thing rubbish A37575 was your post. Cloud cutter said it. I suppose you have some fangdangled way (perhaps a slide rule or markings on the control colomn) to set just the right amount of aileron deflection depending on the steady and never changing crosswind component. You seem like a chap who has no 'feel' for an aircraft. Ever had problems drifting of the centreline immediately after rotate by chance or feel like you're fighting with the aircraft on the ground?

Think you are also forgetting that pilots, and particularly students are creatures of habit and it is prudent for them especially to have a consistent technique to apply in ALL crosswinds.

I'd imagine you've never operated an aeroplane in more than 10 knots of cross and haven't taxied around much in a tail dragger either.

P.s It (15 knots for the 152) is a maximum DEMONSTRATED crosswind component for a short field landing as per the flight manual at MAUW, min approach speed and one of average (rough old PPL's) pilot skill at the controls. It is not a limit for aircraft of these weights.

[Herbie-TZ]

mr Garrison,

As I read your original question, I can see that a principle is applied that can give you an idea of performance.

The principle: At half of your take-off roll you should have 2/3
of your lift-off speed (Vr).

The thing is that you need a pre-determined Airspeed Check-point to assess this properly.

Next to that you need to know the point where you can still safely abort the take-off without the danger of an overrun.
Normally that is about half of the TODA but several factors can change that...

Anyhow what we use is, if during a take-off roll we don't get the
2/3 of lift off speed, it is indicating something is wrong,
either not enough engine power, or the softness of the field is a factor and we will abort the take-off if we are before the "Safe Abort-Point"

Indeed this is for short (&soft) field operations.
The danger is when you would continue with not having reached the e.g. 40 kts that you end up in the trees...

For a long tarmac runway there is normally not a problem, but I still use my speed-check to not get airborne with something wrong...

Hope this helps,

Herb

[tinpis]

I guess slide rule techniques all turn to ****e when the going gets rough.
Witness the A340 "landing" film at Melbourne the other day.
I reckon in the last 200 feet of that balls up there was absolutely no one in control.
:rolleyes:

mack..mack..spelling

[A37575]

Cessna 152 Pilot. What sort of flying school instructor would even think of starting off a new student on circuits with any sort of crosswind? That is not only a highly undesirable introduction to first circuits but a financial rip-off to the student.

[GOATRIDER]

Re: the aileron deflection I talked about- this is only ONE method I use when getting off remote airstrips ie river beds, beaches and strips around 280- 300metres...this is the typr eof flying my job requires and has been for 8 years...its just one method that a 38000hour bush pilot showed me and I find it works. Most aeroclubs will show you the corrects techniques or at least the basics. As for Mr 4spool- get your sorry arse into a 185 and find some small rough airstrips and test the theory you pillock...Lead Balloon- c185 pilot and chimbu- thankyou for your inputs---its all about learnig..the moment you think you know it all you will wind up in a box...nice to know LB that you did some PNG time...

[cessna 152 pilot]

A37575,

As i said where i fly there is only one runway and 9 out of 10 times there is a massive crosswind, so we don't have much choice, about which runway.

For me it is very useful learning to fly in the crosswind, and yes my first lesson was in a strong wind, but i don't see it as a waste of money at all, becuase i have learnt to fly in strong crosswinds, when there is no wind or straight up and down the runway i find it easy as pie.

I feel sorry for some pilots who fly in big airports, and when the wind changes so does the runway. Makes it hard to learn how to land in a crosswind.

I know for a fact that several traning organizations send planes and pilots up to us just to fly in a nice crosswind.

[GOATRIDER]

Good Call C152 pilot...the New Zealand flying training system in some ways is a bit of a farce especially at some of the larger flying schools. For instance we had a CPL/C-cat come to where I fly and couldnt even do a crosswind take off or landing. Probably not the fault of the student, moreso the fault of the institution. Some not all of these institutions are of a conveyer belt type mentality.

[cessna 152 pilot]

I have heard stories of a new CPL pilot flying for a charter company and was told to land in a remote strip, with the passengers for a picnic - some sort of expensive morning tea trip, and had to turn back becuase after several attempts of landing he could not land with the crosswind.

He was ashamed, but tells everyone how strong the wind was. So a few guys went for a fly out there and landed no problem. Then he confessed that he learnt to fly in a big school and they just changed runways.

Don't know what he was doing in the NAV exercises!!!

[hair of the dogma]

First Cessna 152 it is spelt picnic.

You would do well to give those stories the respect they deserve. Usually circulated by somebody trying to make themselves look good, and almost always completely fictional.

You wouldnt happen to be an instructor by any chance would you?

[cessna 152 pilot]

No Hair of the Dogma i am not an instructor, and i have no idea about the truth of the story.

All i know is that an instructor told me that a while ago when i was having a joke about the crosswinds when ever i go flying.

All in all i think that it is fun to fly in a crosswind, Pitty can't walk straight after i get out though i still walking sideways!!!!