C152
C152
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One Fifty Two Speeds
Here goes (aerobat in brackets, all speds IAS):
Vne 149 (172); Vno 111 (125); Va @1670lbs 104 (108); Vfe 85; Vs 40; Vs1 35; Vx clean 55; Vx 10 degrees flap 54; Vy 67; Normal approach 65; Short field approach 54.
Kermie
Vne 149 (172); Vno 111 (125); Va @1670lbs 104 (108); Vfe 85; Vs 40; Vs1 35; Vx clean 55; Vx 10 degrees flap 54; Vy 67; Normal approach 65; Short field approach 54.
Kermie
Kermit. My understanding is that 54 knots is the usual certificated 1.3Vs for the C152. In other words the normal landing speed. After all, the landing distance charts are based upon 54 knots and surely that is what students should be using (calm wind permitting).
I thought all aircraft certification for landing was based broadly on 1.3Vs, for example Chieftain, Seneca, Warrior, B737 and so on. These are the "normal" approach speeds on which their landing charts are based. There is no sweat using these speeds.
So how come the "normal" approach speed you mentioned is 65 Knots in the C152? Seems awfully in excess of the correct manufacturer's recommended threshold speed to me and will lead to considerable float and long touch-down. The so called "short field" landings are an old war-time operational landing at 1.1Vs - same as aircraft carrier landings.
I thought all aircraft certification for landing was based broadly on 1.3Vs, for example Chieftain, Seneca, Warrior, B737 and so on. These are the "normal" approach speeds on which their landing charts are based. There is no sweat using these speeds.
So how come the "normal" approach speed you mentioned is 65 Knots in the C152? Seems awfully in excess of the correct manufacturer's recommended threshold speed to me and will lead to considerable float and long touch-down. The so called "short field" landings are an old war-time operational landing at 1.1Vs - same as aircraft carrier landings.
Moderator
MJ,
That may be the case ... but what Centaurus is highlighting .. and VERY correctly so .... is the fact that the unthinking pilot who
(a) uses a higher speed for landing, recommended or otherwise, being a higher speed than that on which the landing distance data is predicated, and
(b) doesn't do some simple correcting sums for the published landing distance, and
(c) does both of the above going into a critically short bush strip after doing all his/her flying at a major aerodrome
might suffer a fright or worse ..... think about it ... the CP or CFI probably is not going to go along too readily with some tale about using the same speed which worked fine on a 5000 ft strip length....
This is not an academic topic ... the next guy or gal who comes unstuck doing the higher speed approach trick into a paddock strip will have had plenty of antecedent company ....
That may be the case ... but what Centaurus is highlighting .. and VERY correctly so .... is the fact that the unthinking pilot who
(a) uses a higher speed for landing, recommended or otherwise, being a higher speed than that on which the landing distance data is predicated, and
(b) doesn't do some simple correcting sums for the published landing distance, and
(c) does both of the above going into a critically short bush strip after doing all his/her flying at a major aerodrome
might suffer a fright or worse ..... think about it ... the CP or CFI probably is not going to go along too readily with some tale about using the same speed which worked fine on a 5000 ft strip length....
This is not an academic topic ... the next guy or gal who comes unstuck doing the higher speed approach trick into a paddock strip will have had plenty of antecedent company ....
Last edited by john_tullamarine; 12th May 2002 at 02:36.
Kermit. You are right re the POH figures stating normal landing approaches can be made at 55-65 knots flaps down. But 10 knots is quite a wide spread of speeds. As 65 knots will give a real long float, it would seem better to use the lower end of the normal landing speeds ie 54 knots as "normal". That way, the student is in a good position to be able to land on wet grass strips without running off the end into the bushes after a 65 knot float. Also one could argue that if the student is bound for the airline stream he will have to get used to approaching at the 1.3Vs and not adding 10 knots on for prosperity!
Moderator
Kermit,
(a) Be aware that the GAMA POH includes both "approved" and "not approved" data and understand the differences implicit in the distinction.
(b) It might be an idea if you read the data in context and not merely extract numbers without considering the significance of, and real world implications inherent in, their use. So far as the question of distances is concerned, there are more than a few traps lurking out there for young players.
(a) Be aware that the GAMA POH includes both "approved" and "not approved" data and understand the differences implicit in the distinction.
(b) It might be an idea if you read the data in context and not merely extract numbers without considering the significance of, and real world implications inherent in, their use. So far as the question of distances is concerned, there are more than a few traps lurking out there for young players.
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In the good old days of the C150 we all worked in MPH and the standard speed to climb and for final approach was 70. I think this and the rough equivalent of 65 kts in the C152 is used because it makes life in the early days of teaching the landing phase. If a student maked a B**ls up of it when approaching at 1.3Vs you could be bouncing back 10 feet into the air with "nothing on the clock" and an expensive unrecoverable stall to follow. Approach at 70 (65) and the immediate application of power puts you nicely back in the climb and in a few seconds "bloggs" has recovered his composure to take back control and have another go. Such speeds don't matter on a 1000 metre runway, but what may have happened is that when the skill level of the student is sufficiently advanced, insufficient emphasis and traning is given on approaching at 1.3Vs to achieve the "performance" or "short" landing as we used to call it.
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Not a test pilot
The speeds came from the manufacturer's Aircraft Flight Manual. I am unsure what a GAMA Pilot Operating Handbook is.
We experience no problem with float using a 65 knot approach as indicated in the AFM. The runway we use doesnt require a 54 knot full flap approach. The short field approach is taught at a later time as an advanced lesson, due to the nature of many of our airfields.
The guy who taught me used to say you are not a test pilot so use the configurations in the AFM. They are there for a reason. Good advice, for both me and all the 152's I have flown are all unscathed after 600 hours on type.
Kermie
We experience no problem with float using a 65 knot approach as indicated in the AFM. The runway we use doesnt require a 54 knot full flap approach. The short field approach is taught at a later time as an advanced lesson, due to the nature of many of our airfields.
The guy who taught me used to say you are not a test pilot so use the configurations in the AFM. They are there for a reason. Good advice, for both me and all the 152's I have flown are all unscathed after 600 hours on type.
Kermie
Moderator
Kermie,
First, I am not familiar with the NZ manuals for light aircraft so my Australian biased comments may not be entirely appropriate in your neck of the woods. However my understanding is that NZ is even more aligned with the US way of doing things than the Australian scene is rapidly becoming ....
GAMA is the US umbrella manufacturer's group. The document you refer to as the manufacturer's AFM is probably titled the Pilot's Operating Handbook (POH). Parts of the POH are FAA approved and you can take the information with a bit of confidence. Any pages which aren't labelled FAA approved .. aren't ... be wary ... the marketing people get to have a finger in the manual.
You are missing the main point of the discussion. If the FAA pages recommend the higher speed and the landing distance tables indicate that they are based on the higher speed, then I don't have a problem.. if not, check what speed the tables are based on ... do check if the tables are raw data or factored .. that can give a chap a nasty surprise if you get it wrong also .....
This is the problem in Australia since CASA tossed out the old Australian flight manuals. In years gone by the AFM went quite a way to protecting the pilot from his/her lack of certification knowledge ... not so now ... you either know the basis of the numbers ... or you run the risk of getting bitten ... and I suspect that the same situation prevails in NZ.
The concern is not when you are operating at Auckland (got to know that place well a year or two ago) or some other place with lots of runway ... rather when the newish pilot heads off to the bush with his/her newish licence ... and then tries to land into a short bush strip using the techniques which worked OK for the long runways .... but often don't for the short strip surrounded with nasty bits and pieces ...
First, I am not familiar with the NZ manuals for light aircraft so my Australian biased comments may not be entirely appropriate in your neck of the woods. However my understanding is that NZ is even more aligned with the US way of doing things than the Australian scene is rapidly becoming ....
GAMA is the US umbrella manufacturer's group. The document you refer to as the manufacturer's AFM is probably titled the Pilot's Operating Handbook (POH). Parts of the POH are FAA approved and you can take the information with a bit of confidence. Any pages which aren't labelled FAA approved .. aren't ... be wary ... the marketing people get to have a finger in the manual.
You are missing the main point of the discussion. If the FAA pages recommend the higher speed and the landing distance tables indicate that they are based on the higher speed, then I don't have a problem.. if not, check what speed the tables are based on ... do check if the tables are raw data or factored .. that can give a chap a nasty surprise if you get it wrong also .....
This is the problem in Australia since CASA tossed out the old Australian flight manuals. In years gone by the AFM went quite a way to protecting the pilot from his/her lack of certification knowledge ... not so now ... you either know the basis of the numbers ... or you run the risk of getting bitten ... and I suspect that the same situation prevails in NZ.
The concern is not when you are operating at Auckland (got to know that place well a year or two ago) or some other place with lots of runway ... rather when the newish pilot heads off to the bush with his/her newish licence ... and then tries to land into a short bush strip using the techniques which worked OK for the long runways .... but often don't for the short strip surrounded with nasty bits and pieces ...
Last edited by john_tullamarine; 13th May 2002 at 06:06.
P. Pilcher. Methinks you have made quite a drama out of that 1.3Vs landing approach! Presumably, if you have certified the student competent to go solo, he would have previously carried out several uncomfortable landings from which he would have either re-landed by cushioning any bounce (which is the safest and most convenient method) - or carried out a normal go-around.
A bounce caused by a 65 knot late flare and an instinctive stick pull back, would be an impressive sight indeed. A bounce from a touch down speed around 45 knots should be easily rectified. And to touch down around 45 knots in a C152 means a hold off time off around 5-8 seconds from 54 knots over the fence throttle at idle. So what's the problem with 1.3Vs? Its not dangerous - it is a normal landing speed for just about every type of aircraft designed.
On the other hand a flare at 65 knots aiming to touch down just as the stall-warning beeps, necessarily means you have to dissipate 20 knots by floating. No problem with plenty of runway in front of you - but a potential hazard on a shorter airstrip than normal. And do you then add yet another 5-7 knots over the fence for a flapless? That makes it 77 knots which is damned near cruise speed on a hot day for a C152..
Seems an awfully foolish way to land a small training aircraft.
A bounce caused by a 65 knot late flare and an instinctive stick pull back, would be an impressive sight indeed. A bounce from a touch down speed around 45 knots should be easily rectified. And to touch down around 45 knots in a C152 means a hold off time off around 5-8 seconds from 54 knots over the fence throttle at idle. So what's the problem with 1.3Vs? Its not dangerous - it is a normal landing speed for just about every type of aircraft designed.
On the other hand a flare at 65 knots aiming to touch down just as the stall-warning beeps, necessarily means you have to dissipate 20 knots by floating. No problem with plenty of runway in front of you - but a potential hazard on a shorter airstrip than normal. And do you then add yet another 5-7 knots over the fence for a flapless? That makes it 77 knots which is damned near cruise speed on a hot day for a C152..
Seems an awfully foolish way to land a small training aircraft.
Moderator
Guys,
The discussion is going around in circles ..
The concern is not when you are landing on a 5000 ft runway .... doesn't matter how much of a botched job is made of the flare.
However, the normal manufacturer's data is based on next to no float ... and not much flare ... if the data is unfactored or only factored nominally and is not based on the higher "normal" speed, then the "normal" approach speed is (not may .. IS) going to put you beyond the book landing distance figures.
This sort of ignorance has bent more than a few aircraft over the years .. including a business jet in Oz when the rules were changed some years ago ..... Centaurus is not trying to stir an argument .. rather his intention is to highlight a problem which is largely hidden due to the bulk of training operations being conducted from runways which are not distance critical.
The discussion is going around in circles ..
The concern is not when you are landing on a 5000 ft runway .... doesn't matter how much of a botched job is made of the flare.
However, the normal manufacturer's data is based on next to no float ... and not much flare ... if the data is unfactored or only factored nominally and is not based on the higher "normal" speed, then the "normal" approach speed is (not may .. IS) going to put you beyond the book landing distance figures.
This sort of ignorance has bent more than a few aircraft over the years .. including a business jet in Oz when the rules were changed some years ago ..... Centaurus is not trying to stir an argument .. rather his intention is to highlight a problem which is largely hidden due to the bulk of training operations being conducted from runways which are not distance critical.
