Calculating Approach speed --additions
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I have one of the
, and had it installed on my STOL Cessna 150 for a while. I am very impressed with the concept, and experimented quite a lot. What I found though was that my aircraft was capable of flight speeds which were slower than the apparent capability of the system. The pointer just kind of wallowed at low speeds, I suppose because the total dynamic pressure was not quite enough to activate the indicator, so the differential could not be measured diffinatively. I found I could get airborne before I had certain a "fly" indication. It thus left me not totally confident about the information provided on approach at low speeds (the whole reason for having it). Thus I removed it, and it remains on the shelf.
That said, I am still quite impressed with it. On a faster aircraft it would probably work very well. I have a 182 coming up, which perhaps I will experiment on.
As for my 150, I will continue to use a combination of the ASI, and "the force!" on approach. The results are very much to my liking!
Alpha System Lift Reserve Indicator
That said, I am still quite impressed with it. On a faster aircraft it would probably work very well. I have a 182 coming up, which perhaps I will experiment on.
As for my 150, I will continue to use a combination of the ASI, and "the force!" on approach. The results are very much to my liking!
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I would go with the fact that the majority of people are normally running 5-10knts above the book speeds anyway.
If you do an approach speed that is by the book I reckon the majority of instructors would get very twitchy.
The whole point of adding a bit for gusts is because of the momentum of the aircraft and spool up times for engines.
Light aircraft with a petrol donk is virtually instant power and your light there really isn't any need for sticking on 5 to 10 knts because for gusts if your flying visually.
In my icle turboprop I wouldn't start adding anything until over 30knts of gust.
Bigger heavy machines without instant power you need the buffer of carrying some extra energy. In my opinion its not require for your average spam can.
If you do an approach speed that is by the book I reckon the majority of instructors would get very twitchy.
The whole point of adding a bit for gusts is because of the momentum of the aircraft and spool up times for engines.
Light aircraft with a petrol donk is virtually instant power and your light there really isn't any need for sticking on 5 to 10 knts because for gusts if your flying visually.
In my icle turboprop I wouldn't start adding anything until over 30knts of gust.
Bigger heavy machines without instant power you need the buffer of carrying some extra energy. In my opinion its not require for your average spam can.
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Light aircraft with a petrol donk is virtually instant power and your light there really isn't any need for sticking on 5 to 10 knts because for gusts if your flying visually.
A and C
Good lord, is there anything you haven't flown
. Just because you don't like the groundspeed mini system doesn't make it any less valuable as a safety tool!
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If they were taught how to fly properly they wouldn't need a an ASI.
Set the correct attitude trim the bugger and let the aircraft do the work. To many pilots chase the needles instead of letting the aircraft do whats its design to do which is to fly.
If I had a pound for every student/FO that i have told to let go of the controls for suddenly all the turbulence to disappear, the aircraft start tracking in a straight line and for the airspeed to become stable I would be a rich man.
Instrument approaches require a bit more point and power. Visually its over controlling which leads to speed instability in the majority of cases.
My current machine is a 10 tonne TP with 3300SHP on the wings and I fly it excatly the same as a tommahawk on approach. I have a Vat range of 10 knots. But I don't need to worry about it cause its exactly the same picture whatever the weight because your flying an approach angle of attack on the wings. Set the picture, power as required to keep the decent profile and bobs your uncle the speed is right.
Please note flying on instruments requires more of a point and power technique my comments only refer to approaches flown visually.
Set the correct attitude trim the bugger and let the aircraft do the work. To many pilots chase the needles instead of letting the aircraft do whats its design to do which is to fly.
If I had a pound for every student/FO that i have told to let go of the controls for suddenly all the turbulence to disappear, the aircraft start tracking in a straight line and for the airspeed to become stable I would be a rich man.
Instrument approaches require a bit more point and power. Visually its over controlling which leads to speed instability in the majority of cases.
My current machine is a 10 tonne TP with 3300SHP on the wings and I fly it excatly the same as a tommahawk on approach. I have a Vat range of 10 knots. But I don't need to worry about it cause its exactly the same picture whatever the weight because your flying an approach angle of attack on the wings. Set the picture, power as required to keep the decent profile and bobs your uncle the speed is right.
Please note flying on instruments requires more of a point and power technique my comments only refer to approaches flown visually.
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The problem is thus: We are taught a 'safe' approach speed - it's normally a bit more than 1.3 Vso, for 'safety'. Then we add a bit for the wind, a bit for the gust, and a bit for mother/wife/kids, uncle tom cobley and all.
Another factor usually forgotten is that your 'book' stall speeds are based on max gross weight. They reduce as you reduce the a/c weight, so your landing speeds should reduce accordingly.
You finish up with a bunch of people dragging something like a PA28 over the hedge at 75 kts with full flap (and I know people who go faster). There lies the road to broken nosewheels as well as holes in the hedge.
Frankly we're taught so much to fear the stall, I believe there's far more of a danger of people going off the far end than stalling in - how many accident reports have you seen recently where someone with a functioning engine come up short? You've also got a pretty good AOA indicator in the cockpit of every plane I've ever flown.. here's a clue.. it's right in your hand
P.S. I'm a weekend warrior too...
Another factor usually forgotten is that your 'book' stall speeds are based on max gross weight. They reduce as you reduce the a/c weight, so your landing speeds should reduce accordingly.
You finish up with a bunch of people dragging something like a PA28 over the hedge at 75 kts with full flap (and I know people who go faster). There lies the road to broken nosewheels as well as holes in the hedge.
Frankly we're taught so much to fear the stall, I believe there's far more of a danger of people going off the far end than stalling in - how many accident reports have you seen recently where someone with a functioning engine come up short? You've also got a pretty good AOA indicator in the cockpit of every plane I've ever flown.. here's a clue.. it's right in your hand
P.S. I'm a weekend warrior too...
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If I had a pound for every student/FO that i have told to let go of the controls for suddenly all the turbulence to disappear, the aircraft start tracking in a straight line and for the airspeed to become stable I would be a rich man.
That was me exactly,he also told me I was holding the yoke like it was a cobra about to strike me.
I let go,and hey presto,the turbulence dissapeared.
Amazing,must be Magic
That was me exactly,he also told me I was holding the yoke like it was a cobra about to strike me.
I let go,and hey presto,the turbulence dissapeared.
Amazing,must be Magic
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I tend not to use "numbers" so much when coming in to land, even the altimeter. I join the circuit at the correct height and speed and from that moment on don't use the altimeter at all (as long as I can see the runway). Regarding airspeed, I glance at the ASI occasionally to make sure that I am not getting hideously slow but most of the time one can set power and feel the aeroplane and see where you're going to touch down and adjust that based upon the winds. Too slow and sink rate increases and it becomes sloppy, too fast and you'll overshoot the TD point. As long as you pitch for speed you won't stall.
One really useful bit of training I did years ago when I did my Commercial (I had a great instructor who was highly experienced) was to take off and then the FI covered all the instruments, except for oil pressure and oil temp. He then made me come in and land. In a varying theme on this he then made me do the above without touching the yoke, but only using rudder and trim. I'd highly recommend some advanced training to anyone who has their PPL...
One really useful bit of training I did years ago when I did my Commercial (I had a great instructor who was highly experienced) was to take off and then the FI covered all the instruments, except for oil pressure and oil temp. He then made me come in and land. In a varying theme on this he then made me do the above without touching the yoke, but only using rudder and trim. I'd highly recommend some advanced training to anyone who has their PPL...
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One of the most annoying type of pilot is the " roller coaster " pilot that constantly pitches up and down because they are airspeed chasers.
And that mishandling of the controls comes from poor instructors who were taught by poor instructors......
And that mishandling of the controls comes from poor instructors who were taught by poor instructors......
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I wish I had all you lot sat in with me last Saturday. I hit sink / wind shear / rota turbulance on a crosswind past trees and decided it was too much. Fully fine and full throttle we were dropping like a lift.
Could have done with some ideas.
Could have done with some ideas.
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I wish I had all you lot sat in with me last Saturday. I hit sink / wind shear / rota turbulance on a crosswind past trees and decided it was too much. Fully fine and full throttle we were dropping like a lift.
Could have done with some ideas.
Could have done with some ideas.
For instance was there any indication during the approach that that situation existed?
Another factor usually forgotten is that your 'book' stall speeds are based on max gross weight. They reduce as you reduce the a/c weight, so your landing speeds should reduce accordingly.
I flew the plane from Toronto to Philadelphia. Landing at Wings Field the airplane did not want to come down. With not much fuel in the tanks, I went around the first time and touched down two thirds down the runway the second time. I would have gone around a second time but the runway elevation had an upslope two thirds the way down.
Quite a few knots too fast for the low weight
These days I prefer steeper approaches. If you suddenly need great gobs of power to maintain your chosen approach slope, you have allowed yourself to get suckered.
Glider flying is a good cure for those prone to two mile finals in SEPs; mind you there's not much in the way of a weight change affecting approach speed as long as you've remembered to dump the water ballast.
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On landing at book speed I stalled in the flare a little higher than expected.
A look at the Flight manual showed I had gone overgross -- don't trust instructors not to set you up
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Here's a question for the panel.
If one is landing in a 10kt headwind (straight down the runway) at 150ft, and this suddenly reduces to zero, what is the effect on the aircraft's airspeed, groundspeed, rate of descent, angle of descent and touchdown point, assuming that no changes are made to power or attitude?
OK, it's somewhat theoretical, but serves to illustrate the thought.
Similarly, what would the answers be if one was in the same situation in still air, and a sudden headwind of 10kts appeared?
If you want to take a specific, assume 1.3Vs = 60kt, and ROD = 300 fpm, just to make the math easier.
WW
If one is landing in a 10kt headwind (straight down the runway) at 150ft, and this suddenly reduces to zero, what is the effect on the aircraft's airspeed, groundspeed, rate of descent, angle of descent and touchdown point, assuming that no changes are made to power or attitude?
OK, it's somewhat theoretical, but serves to illustrate the thought.
Similarly, what would the answers be if one was in the same situation in still air, and a sudden headwind of 10kts appeared?
If you want to take a specific, assume 1.3Vs = 60kt, and ROD = 300 fpm, just to make the math easier.
WW
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I don't know what the thought is, but to calculate, you would need some pretty clever maths as mass and inertia need to be considered.
In the first instance the a/c would reduce to 50kts (instantaneously, and still above the 46kt stall, even assuming you're magically landing at MGW) it would now be out of trim, pitch nose down and fall under glide accelerating. Once returned to 60kts it would have a flatter glide relative to the ground, therefore the affect on touchdown etc would depend upon the inertia and the altitude at which the shear occurred.
If you assumed the a/c to have no inertia, it would maintain 60kt and finish up touching down long
In the reverse instance it would initially balloon over glide, then commence a steeper glideslope. Again whether it fell short or long would depend upon inertia and shear altitude.
It's also somewhat irrelevant 'cos any pilot who is half on the ball should react to correct, and possibly even anticipate!
In the first instance the a/c would reduce to 50kts (instantaneously, and still above the 46kt stall, even assuming you're magically landing at MGW) it would now be out of trim, pitch nose down and fall under glide accelerating. Once returned to 60kts it would have a flatter glide relative to the ground, therefore the affect on touchdown etc would depend upon the inertia and the altitude at which the shear occurred.
If you assumed the a/c to have no inertia, it would maintain 60kt and finish up touching down long
In the reverse instance it would initially balloon over glide, then commence a steeper glideslope. Again whether it fell short or long would depend upon inertia and shear altitude.
It's also somewhat irrelevant 'cos any pilot who is half on the ball should react to correct, and possibly even anticipate!
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In the first instance the a/c would reduce to 50kts
WW
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Nope. There's a nasty little thing called inertia - the tendancy of a body in motion to continue so. (sorry, yes, 50kts airspeed)
It's pretty complicated, and you soon get into territory I don't understand, mythical downwind turns, loss of airspeed and such, but, suffice to say if you're flying at 60kts into a 60kt headwind, and someone turns off the headwind, you will *NOT* have 60kts on the ASI. You'll have an uncomfortable fall for a while until you overcome your inertia and start flying again - assuming the ground does not intervene!
Otherwise we could all fly in at 5kts above the stall and not worry
It's pretty complicated, and you soon get into territory I don't understand, mythical downwind turns, loss of airspeed and such, but, suffice to say if you're flying at 60kts into a 60kt headwind, and someone turns off the headwind, you will *NOT* have 60kts on the ASI. You'll have an uncomfortable fall for a while until you overcome your inertia and start flying again - assuming the ground does not intervene!
Otherwise we could all fly in at 5kts above the stall and not worry
On landing at book speed I stalled in the flare a little higher than expected.
Do you mean you were a little higher above the runway when the airplane stalled, or do you mean it stalled at a higher indicated airspeed?
A look at the Flight manual showed I had gone overgross -- don't trust instructors not to set you up
If the instructor set you up and he/she knew the airplane was over legal gross weight why did he/she fly in it?
Do you mean you were a little higher above the runway when the airplane stalled, or do you mean it stalled at a higher indicated airspeed?
A look at the Flight manual showed I had gone overgross -- don't trust instructors not to set you up
If the instructor set you up and he/she knew the airplane was over legal gross weight why did he/she fly in it?
I was more trusting of instructors at that stage of my career and never thought an instructor would ever suggest anything outside the regs. What was going on in the instructor's mind a couple decades ago I have no idea. It was a good lesson for me, even though poorly delivered.
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Bearing in mind, an aeroplane can stall at any airspeed, any altitude and any attitude...... I've seen the ASI read zero at 3000' and not been stalled....
PS we all know that aeroplanes fly perfectly well over max weight
I've seen the ASI read zero at 3000' and not been stalled....PS we all know that aeroplanes fly perfectly well over max weight
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1.3 is a good figure to work with. My own experience has taught me that even if the wind is gusty with a properly trimmed aeroplane (thats elevator power and rudder) then you only have to react to gusts, turbulence or wind shear. I flew the tug aeroplane for a gliding club in my early hours of flying (to gain experince and hours), that was from a hilltop site which was prone to lots of turbulence. You soon learn to follow the trend rather than trying to fly every tiny movement of the instruments. You react to the big events and ignore the little events unless they develop into a trend.
When its very windy my prefered technique is to do an approach with less flap, that way you have a higher approach speed (at 1.3vso) and the aircraft is more reactive to control input should you need to do something quickly. Yes the approach is shallower than full flap but given the wind, you should still be at a sensible angle of approach, relative to the runway. Try doing a flapless landing on a calm day and then on a windy day, you will see what I mean about the angle of approach. If you dont understand what I mean draw out a triangle of velocities and you will see - the hypotenuse being the airspeed, the base being the relative groundspeed,
It seems to me that the perpetual argument about an aircraft flying in a different way in a wind continues - how does the aircraft know its going downwind or into wind? The groundspeed alters but not the airspeed, turbulence increases low level in stronger winds. Your speed should remain the same (1.3vso) your approach technique (amount of flap and/or sideslip) should alter dependant on the turbulence, crosswind and strength of wind and known turbulence / gustiness, not the approach speed (1.3Vso)
My answer to Woy Rogers question is that if the wind suddenly dropped then your airspeed would remain the same, your approach angle shallower and you would land further along the runway. Has anyone done the inertia / mass sums v groundspeed, the difference a sudden loss of a headwind makes to the sums does not really affect airspeed, only groundspeed to any significant amount, I cant fly accuratly to 0.01kts....
When its very windy my prefered technique is to do an approach with less flap, that way you have a higher approach speed (at 1.3vso) and the aircraft is more reactive to control input should you need to do something quickly. Yes the approach is shallower than full flap but given the wind, you should still be at a sensible angle of approach, relative to the runway. Try doing a flapless landing on a calm day and then on a windy day, you will see what I mean about the angle of approach. If you dont understand what I mean draw out a triangle of velocities and you will see - the hypotenuse being the airspeed, the base being the relative groundspeed,
It seems to me that the perpetual argument about an aircraft flying in a different way in a wind continues - how does the aircraft know its going downwind or into wind? The groundspeed alters but not the airspeed, turbulence increases low level in stronger winds. Your speed should remain the same (1.3vso) your approach technique (amount of flap and/or sideslip) should alter dependant on the turbulence, crosswind and strength of wind and known turbulence / gustiness, not the approach speed (1.3Vso)
My answer to Woy Rogers question is that if the wind suddenly dropped then your airspeed would remain the same, your approach angle shallower and you would land further along the runway. Has anyone done the inertia / mass sums v groundspeed, the difference a sudden loss of a headwind makes to the sums does not really affect airspeed, only groundspeed to any significant amount, I cant fly accuratly to 0.01kts....
Please read the comments of A and C and bose-x - with which I agree wholeheartedly!
Fly the aeroplane as per POH and do NOT add ANYTHING for gusts, wind, people in the back, plagues of frogs or anything else UNLESS the POH so advises!
Some years ago, after a couple of damaging incidents, we reviewed our guidance and insisted on correct approach speeds as per POH. Thereafter we had not a single problem.
Too many people are keen to export half-understood people-tube techniques to little spamcans. DON'T!! The POH is the ONLY reference you should be using.
Fly an accurate POH approach speed with the 'point-and-power' technique and you won't go wrong.
Fly the aeroplane as per POH and do NOT add ANYTHING for gusts, wind, people in the back, plagues of frogs or anything else UNLESS the POH so advises!
Some years ago, after a couple of damaging incidents, we reviewed our guidance and insisted on correct approach speeds as per POH. Thereafter we had not a single problem.
Too many people are keen to export half-understood people-tube techniques to little spamcans. DON'T!! The POH is the ONLY reference you should be using.
Fly an accurate POH approach speed with the 'point-and-power' technique and you won't go wrong.