Approach Speed in GA Aircraft
Well it does matter when you are flying commercially into short strips.
Ex 2B in the Canadian Flight Test Guide: https://tc.canada.ca/en/aviation/pub...-tp-13462#ex2b
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Your ability to track down the various iterations of the regs is impressive.
I've done a fair amount of position error correction flying. I have a program coming up in a week or so on a AS350 helicopter with a previously approved external assembly, which is suspected of inducing a PEC error (static port partly obscured by the mod). My work to approve a new pitot tube and static port arrangement on the DC-3T's in Germany has been put off until next year. That will involve a lot of flying, and some fiddling with static ports to get within the required limits of error (it has too much right now to be approved, so the original system is still in use).
Interestingly, while I was test flying an older Cessna 210 last week, following a massive repair I had to approve, I noticed that the operation of the landing gear momentarily affected the static ports, and induced a bounce in the altimeter and VSI. After landing I had a look and noticed that Cessna had placed the static ports up and behind the main gear doors. Obviously, with the main gear doors open, there is a static disturbance. But, the doors close again after the gear extends, so it's not really a problem, as long as you're aware.
If the manual tells you to approach at 1.4Vs, for example, then OK. But if the manuals recommends 1.3 and your airclub 1.6, what then ?
Simple, you fly the aeroplane in accordance with the POH/AFM. No one including flying/schools/clubs or any other "operator" have the right to demand anything different.
Simple, you fly the aeroplane in accordance with the POH/AFM. No one including flying/schools/clubs or any other "operator" have the right to demand anything different.
Jan - It is of no consequence whether the aircraft is flown by a commercial pilot for commercial operations or flown by a private pilot for private purposes: It is still the same aircraft and therefore it flies the same.
For the CPL skill test and throughout the training the operation of the aeroplane must be strictly in accordance with the aircrafts POH. Whether flown by a CPL or a PPL it is the deviations from the correct ops that lead to accidents.
For the CPL skill test and throughout the training the operation of the aeroplane must be strictly in accordance with the aircrafts POH. Whether flown by a CPL or a PPL it is the deviations from the correct ops that lead to accidents.
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Average SEP 65/70 knots ...end of
In real world operations, if you are 5 mile back on the ILS, you are almost always above Vmca, so it's not a concern. At one mile from the threshold, when you start slowing down to Vref, you are generally committed to landing, hence there is no possibility that you would need to apply 100% power to the operative engine in the event of an engine failure.
My comments are based on thousands of hours in a 12,500 pound twin turboprop, but I think the same concepts would apply to most light twin engine aircraft.
Yes, I agree, noting that this requirement is for a latest FAR Par 23 certified plane, but is not a requirement for a CAR 3 or older 23.1581. CAR 3.777 makes no mention of IAS/CAS. CAR 3.778(a) also makes no mention, though points you to 3.757, which refers to TAS (just add to the confusion, I suppose!). 23.1581 does not seem to mention IAS until revision 23-50 of 1996. So any plane certified prior to that would not have to comply.
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Thanks for the answer! I fly a Baron 58 and your comment describes exactly what we do. Since the main purpose of this topic is to talk about speed management regarding weight, the first thing that I was thinking was about Vmca.
We always follow the speed published by the manufacturer, the difference is the % of power we use to maintain the approach speed. Basically, the approach speed will be the same, with less or more weight. - Talking about light twins.
As an example, Flight Safety recommends flying base leg with 110 KIAS (Baron G58, visual approach). The Vref is 95 KIAS and Vmca 84 KIAS. The MTOW is 5,500 lbs.
We always follow the speed published by the manufacturer, the difference is the % of power we use to maintain the approach speed. Basically, the approach speed will be the same, with less or more weight. - Talking about light twins.
As an example, Flight Safety recommends flying base leg with 110 KIAS (Baron G58, visual approach). The Vref is 95 KIAS and Vmca 84 KIAS. The MTOW is 5,500 lbs.
"Average SEP 65/70 knots ...end of.
If I approach at this speed in my SEP, I will usually go through the far hedge unless I have the good sense to go around and try again at the correct approach speed for my aircraft (around 50 knots.)"
Can the approach speed in a low-inertia aircraft be too high, provided the "at threshold" speed is achieved? It can be too low.
If I approach at this speed in my SEP, I will usually go through the far hedge unless I have the good sense to go around and try again at the correct approach speed for my aircraft (around 50 knots.)"
Can the approach speed in a low-inertia aircraft be too high, provided the "at threshold" speed is achieved? It can be too low.
Well Mouraigh1, as the saying goes "it's only the last nanometer that matters" but, this is much too easy to say. Most accidents/incidents come about because of an unforeseen event culminating in a distraction and pilot overload. Sod's law tells us that Sod is always around just waiting for his moment to strike. For the most part poorly applied approaches more often than not do not lead to an accident but that is usually down to fortune: i.e. Sod being pre-occupied elsewhere. If you follow 'Murphy's law Sod won't always be elsewhere. I suggest you take a look at James Reason's 'Swiss Cheese Model'. It is worth a google.
A stable well flown approach will always maximise the cognitive reserve to enable the pilots to deal with the unexpected and thus avoid the slips and errors which are always a major ingredient of accidents.
A stable well flown approach will always maximise the cognitive reserve to enable the pilots to deal with the unexpected and thus avoid the slips and errors which are always a major ingredient of accidents.
The POH /AFM are usually the best source for numbers .
The difference between IAS ,CAS and TAS in GA are so small that it is really and truly Academic.
A-Question may arise as to “when “you might choose to use a speed other than flight tested and approved by the sky gods .
Gusty conditions and Cross winds you might want to add some airspeed to give a little bit more control .
Aircraft might be damaged and it starts to do weird stuff when you slow down . I had the top corner of a windscreen depart in a spin . The slowest speed I could get and still have pitch control was 90 KIAS , so I landed at 90 . I was surprised how quickly it stopped on the ground . I was expecting to go off the end . But the drag from the big hole slowed the plane in under 2000 feet .
Changes were made to a few aircraft window seals after that flight .
General rule is you never want to be slower than the POH recommended speeds .I flew with a guy who used really slow speeds for short fields , but you would never deliberately land somewhere that was so short you could not get out again . Almost a helicopter approach . I Showed him how to land a 172 in 150 of ground . It was fun but the slightest turbulence and it would have got expensive real quick . Pointless exercise as you need at least three times that to get into ground effect for departure in a light plane into wind .
Many students get the airspeed covered in the circuit to prove that the airplane can be flown without the airspeed indicator working , you just have to give yourself more room and do not rush the approach .
Time to Fly
The difference between IAS ,CAS and TAS in GA are so small that it is really and truly Academic.
A-Question may arise as to “when “you might choose to use a speed other than flight tested and approved by the sky gods .
Gusty conditions and Cross winds you might want to add some airspeed to give a little bit more control .
Aircraft might be damaged and it starts to do weird stuff when you slow down . I had the top corner of a windscreen depart in a spin . The slowest speed I could get and still have pitch control was 90 KIAS , so I landed at 90 . I was surprised how quickly it stopped on the ground . I was expecting to go off the end . But the drag from the big hole slowed the plane in under 2000 feet .
Changes were made to a few aircraft window seals after that flight .
General rule is you never want to be slower than the POH recommended speeds .I flew with a guy who used really slow speeds for short fields , but you would never deliberately land somewhere that was so short you could not get out again . Almost a helicopter approach . I Showed him how to land a 172 in 150 of ground . It was fun but the slightest turbulence and it would have got expensive real quick . Pointless exercise as you need at least three times that to get into ground effect for departure in a light plane into wind .
Many students get the airspeed covered in the circuit to prove that the airplane can be flown without the airspeed indicator working , you just have to give yourself more room and do not rush the approach .
Time to Fly
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The difference between IAS ,CAS and TAS in GA are so small that it is really and truly Academic.
I try to keep it simple when training other pilots . I just use KIAS when I am sat in the aircraft .
I am not trying to dumb it down too much just not trying to reduce workload and keep it simple .
At the end of the day the indicated airspeed is the easiest number to use . Most of the trainers I have flown the differences was usually less than the thickness of the airspeed indicator needle above 60 kias.
Although it is possible to land a Cessna 152 with no airspeed indicated , fun demo for other instructors , I have rarely demonstrated students that because once they are in ground effect the dials can be a distraction and at that point it is better to pay attention to flying the aircraft .
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I am not trying to dumb it down too much just not trying to reduce workload and keep it simple .
At the end of the day the indicated airspeed is the easiest number to use . Most of the trainers I have flown the differences was usually less than the thickness of the airspeed indicator needle above 60 kias.
Although it is possible to land a Cessna 152 with no airspeed indicated , fun demo for other instructors , I have rarely demonstrated students that because once they are in ground effect the dials can be a distraction and at that point it is better to pay attention to flying the aircraft .
Time to Fly
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Most of the trainers I have flown the differences was usually less than the thickness of the airspeed indicator needle above 60 kias.
When I was checking new Mooney pilots for insurance checks , the difference between normal cruise and Va was interesting .
The Piper Meriden had quite a difference between normal cruise and Va . Both popular private aircraft .
Both aircraft had over forty knots to lose if you got into rough air or it could make life uncomfortable in the Mooney , in the early Piper Meriden the wings would fold . The FAA issued an Ad and got it fixed .
Most Aircraft get uncomfortable above Va in rough air and I only recommend flying above Va or Vb if you like to scare yourself , scare your passengers or you enjoy cleaning vomit out of airplane ceilings and carpets . Or like wrinkles in your aircraft skin to match your wrinkles ?
I am always close to Va if I am near Strato fractus ,big winds or near mountains , just a personal preference . People never remember the extra minutes the flight takes , but they will remember the scarey bumps if you do not respect Va .
The old Cessna airspeed indicators used to have a yellow arc . Top of the arc if you were heavy , bottom of the arc if you were light made Va simple .
i do not understand why they stopped painting the yellow arc on the airspeed indicators . How expensive is yellow paint ?
The Piper Meriden had quite a difference between normal cruise and Va . Both popular private aircraft .
Both aircraft had over forty knots to lose if you got into rough air or it could make life uncomfortable in the Mooney , in the early Piper Meriden the wings would fold . The FAA issued an Ad and got it fixed .
Most Aircraft get uncomfortable above Va in rough air and I only recommend flying above Va or Vb if you like to scare yourself , scare your passengers or you enjoy cleaning vomit out of airplane ceilings and carpets . Or like wrinkles in your aircraft skin to match your wrinkles ?
I am always close to Va if I am near Strato fractus ,big winds or near mountains , just a personal preference . People never remember the extra minutes the flight takes , but they will remember the scarey bumps if you do not respect Va .
The old Cessna airspeed indicators used to have a yellow arc . Top of the arc if you were heavy , bottom of the arc if you were light made Va simple .
i do not understand why they stopped painting the yellow arc on the airspeed indicators . How expensive is yellow paint ?
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The old Cessna airspeed indicators used to have a yellow arc . Top of the arc if you were heavy , bottom of the arc if you were light made Va simple .
i do not understand why they stopped painting the yellow arc on the airspeed indicators . How expensive is yellow paint ?
i do not understand why they stopped painting the yellow arc on the airspeed indicators . How expensive is yellow paint ?
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The old Cessna airspeed indicators used to have a yellow arc . Top of the arc if you were heavy , bottom of the arc if you were light made Va simple...i do not understand why they stopped painting the yellow arc on the airspeed indicators . How expensive is yellow paint ?
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The old Cessna airspeed indicators used to have a yellow arc . Top of the arc if you were heavy , bottom of the arc if you were light made Va simple .
i do not understand why they stopped painting the yellow arc on the airspeed indicators .
i do not understand why they stopped painting the yellow arc on the airspeed indicators .
The beginning of yellow arc on the airspeed indicator is the maximum structural cruising speed (Vno). Faster than that speed, a prescribed gust (by design standard) could overstress the plane without pilot input. Hence the limitation that flight at speeds in the yellow arc be conducted with caution in smooth air only (meaning avoid turbulent air, and don't handle the controls roughly).
The top of the yellow arc is Vne, it is certain that at Vne, you are well above Va at any weight, so you should already be being very gentle on the controls.
For some engines on the Cessna's the white arc goes all the way down to 0. For some it doesn't.