MERGED power curve / floats posts

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photofly
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Re: Float flying techniques for the seasoned bush pilot

Post by photofly »

Why isn't taking off one wheel first a "regular" technique for taking off in a small land plane in a strong crosswind? At first glance that would be the obvious way to do it, that is, just the opposite of a crosswind landing.
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Sockpuppet
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Re: The backside of the power curve

Post by Sockpuppet »

trey kule wrote: Mon Nov 19, 2018 11:42 am Relax Sockster, you have been trolled. All he is looking for is a response so he can ponificate and share his wisdom.
You are being lectured on aerodynamics from someone who joined AvCanada about 10 months ago....as an AME. And who has since morphed into a self certified test pilot lecturing to the unwashed on aerodynamics, and more recently, as a sage float pilot.
The guy is amazing. I, for one, look forward to learning from his disproving literally everybody else’s opinions. Check out his thread on floats where he lectures to those like . on how to fly floats. You just gotta appreciate him.
Oh, I know, but if he doesn't get fed then all of us won't continue to learn from his expertise.
He didn't join 10 months ago, he just pulled this new sock out of the drawer(hence my name). He's been here for years.
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C.W.E.
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Re: Float flying techniques for the seasoned bush pilot

Post by C.W.E. »

Why isn't taking off one wheel first a "regular" technique for taking off in a small land plane in a strong crosswind?
Hydrodynamic drag?
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Zaibatsu
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Re: The backside of the power curve

Post by Zaibatsu »

The reason you don’t take off with one wheel is because the wheels are what are keeping you aligned with the runway. Try taking off with a CRFI under 0.2 with a crosswind to see the effects traction has on crosswinds. Since traction is so effective on dry pavement, we don’t want any lateral movement when the plane touches down because that will induce massive side loads so we control drift with bank and touch down on the upwind wheel.

On a float plane. No reason to takeoff with one wing low except for rolling a float to reduce adhesion. Landing on one performs the same function as landing on one wheel, provided your at a small enough lake where you couldn’t simply take the headwind.
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photofly
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Re: The backside of the power curve

Post by photofly »

Zaibatsu wrote: Mon Nov 19, 2018 2:52 pm The reason you don’t take off with one wheel is because the wheels are what are keeping you aligned with the runway.
I'm afraid I don't understand what you mean. Or at least, if I do understand what you mean, I don't see why that's a problem.

We can all do a graceful crosswind landing by putting the aircraft into a sideslip, and touching down - wheels aligned with the direction of motion - upwind wheel first.
Why don't we reverse that procedure, lift the downwind wheel first and transition into a sideslip, keeping the wheels aligned with the direction of motion, and then lift the other wheel while maintaining the sideslip? The wheels will stay aligned with the direction of motion throughout.

Imagine you were half-way through a textbook landing in a crosswind, with the upwind wheel just touching down, when a rhinoceros ran out of the bushes ahead of you, and you were forced to pull up and go around. You'd maintain your sideslip, pick up the wheel that was in contact with the runway, climb a few feet or a few tens of feet, then transition to coordinated flight before climbing away. Why not take off like that in the first place?
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hotdog1
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Re: MERGED power curve / floats posts

Post by hotdog1 »

Well since the topics are merged it now fits perfectly into my techniques I’ve been wanting to use for decades. I, like the op, once talked to some guys in fort Frances and like the op I couldn’t believe they weren’t aware of my advanced technique. I will attempt to explain for all the inexperienced pilots out there.
I don’t worry about lifting one wheel off the runway for crosswinds, it’s too hard to steer with one main wheel on the ground. To counteract crosswinds on wheels I simply use float techniques of raising one float. Yes, you heard that right!! Hard to believe no one else does this!!!
I just leave the floats on all year round, the added friction is really good at keeping straight in a strong crosswind on a runway!!
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digits_
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Re: The backside of the power curve

Post by digits_ »

photofly wrote: Mon Nov 19, 2018 2:57 pm Imagine you were half-way through a textbook landing in a crosswind, with the upwind wheel just touching down, when a rhinoceros ran out of the bushes ahead of you, and you were forced to pull up and go around. You'd maintain your sideslip, pick up the wheel that was in contact with the runway, climb a few feet or a few tens of feet, then transition to coordinated flight before climbing away. Why not take off like that in the first place?
Not sure if I'm missing multiple levels of sarcasm or rhetoric questions, but don't you generally lift one wheel before the other in a crosswind take-off? It's not a goal per se, but it seems to be a common result from the "stick in the wind" technique. If you are a little late putting the ailerons back to neutral, one wheel will lift of before the other. It's a bit more gentle and for a shorter period of time than on floats, but it does happen.
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ahramin
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Re: MERGED power curve / floats posts

Post by ahramin »

Digits, you're missing the effect that scrantons have with your technique.
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photofly
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Re: MERGED power curve / floats posts

Post by photofly »

No. Classical crosswind takeoff technique is to start the roll ailerons into the wind, smoothly bringing them them to arrive at neutral aileron when the airspeed reaches five or so knots faster than a regular takeoff speed with a small amount of forward pressure, then back elevator to crisply unstick the aircraft from the ground with level wings, after which one allows or assists the aircraft to nose into the relative airflow and assume a crab which represents coordinated flight, tracking the runway centreline.

Per the 172N POH, for example:
781813C0-3EE9-4E66-A2C5-D201665ACD4D.jpeg
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Nothing about one wheel first.

I’m asking why we don’t deliberately try to lift one wheel first. Convention? Or is there some horrible downside that isn’t clear to me?
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digits_
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Re: MERGED power curve / floats posts

Post by digits_ »

If that is the only part about crosswind takeoffs, there is nothing about turning the ailerons into the wind either?

I don't see any downside, and I've never met an instructor or pilot who has seen any downsides either. So not sure who objects to it.

On the water in an underpowered airplane, it is pretty much a requirement on a hot day to lift one float to gain some extra performance. But that doesn't prohibit you from doing it on wheels. It could be described as maybe a bit more challenging for the pilot, but not by much I'd say.
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youhavecontrol
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Re: MERGED power curve / floats posts

Post by youhavecontrol »

photofly wrote: Mon Nov 19, 2018 5:46 pm I’m asking why we don’t deliberately try to lift one wheel first. Convention? Or is there some horrible downside that isn’t clear to me?
I wouldn't say that I TRY to lift one wheel first on crosswind take-off, but it usually ends up happening as a result of the control inputs. I can't see any sizeable benefit other than directional control to wheels lifting off at different times.

Floats on the other-hand... I've definitely heard of people lifting one float first to reduce the water-contact drag, to help accelerate and lift-off easier ... but I've also heard of pilots taxiing around to create a wake first before starting the take-off so the choppy water helps break up the water's contact on the floats... and i've also heard of pilots even doing a slow-turning take-off, where they are in a constant turn, reducing the linear distance of the take-off while also lifting one float first.

Whatever is safe and works I guess. I would love to fly floats one day.
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aeroncasuperchief
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Re: MERGED power curve / floats posts

Post by aeroncasuperchief »

I call bullshit on you flying backside approaches using ground speed as a reference, or that you claim you do them because they are stable
WHERE did I say I used GS as a reference for BS approaches? Or that I claimed they are stable? I will eat those foolish statements If I had written them !

I call bullshit on YOU !
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aeroncasuperchief
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Re: MERGED power curve / floats posts

Post by aeroncasuperchief »

What kind of aircraft do you test fly?
Bearhawk not a bearcat my bad!
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C.W.E.
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Re: MERGED power curve / floats posts

Post by C.W.E. »

But that doesn't prohibit you from doing it on wheels. It could be described as maybe a bit more challenging for the pilot, but not by much I'd say.

These discussions never fail to amaze me.

It is hardly challenging it is a basic airplane handling skill.

If it is challenging for a pilot you need to get some proper flight instructing from someone who understands basics.
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pelmet
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Re: MERGED power curve / floats posts

Post by pelmet »

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Last edited by pelmet on Mon Nov 19, 2018 7:34 pm, edited 4 times in total.
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rookiepilot
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Re: The backside of the power curve

Post by rookiepilot »

photofly wrote: Mon Nov 19, 2018 2:57 pm
Imagine you were half-way through a textbook landing in a crosswind, with the upwind wheel just touching down, when a rhinoceros ran out of the bushes ahead of you, and you were forced to pull up and go around. You'd maintain your sideslip, pick up the wheel that was in contact with the runway, climb a few feet or a few tens of feet, then transition to coordinated flight before climbing away. Why not take off like that in the first place?
There aren't rhinoceros at YTZ. I could've been lucky when I've been there, though.
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pelmet
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Re: MERGED power curve / floats posts

Post by pelmet »

pelmet wrote: Mon Nov 19, 2018 2:16 am
aeroncasuperchief wrote: Sun Nov 18, 2018 8:41 pm
What kind of aircraft do you test fly?
The last one was a Bearcat
It is an interesting looking aircraft. Rotax 582? Never had a chance to fly one. What kind of recommended approach speed versus STOL approach speed?
aeroncasuperchief wrote: Mon Nov 19, 2018 9:03 am Its got an 0-540 Lycoming
Sockpuppet wrote: Mon Nov 19, 2018 10:43 am Maybe you mean a bearhawk, not a bearcat?
aeroncasuperchief wrote: Mon Nov 19, 2018 6:53 pm Bearhawk not a bearcat my bad!
Does kind of look like you got caught out. Most people know the name of the aircraft they are flying and don't mix it up with others, even if they sound similar. The Bearhawk does have a Rotax. Are you trolling.

Many are believing you any more.

I am willing though.......

How about some details on your typical first flight test of the Bearhawk with details about systems and procedures.

Could be interesting info.
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Last edited by pelmet on Fri Jul 08, 2022 5:35 am, edited 1 time in total.
CpnCrunch
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Re: MERGED power curve / floats posts

Post by CpnCrunch »

pelmet wrote: Mon Nov 19, 2018 7:33 pm
Does kind of look like you got caught out. Most people know the name of the aircraft they are flying and don't mix it up with others, even if they sound similar. The Bearcat does have a Rotax. Are you trolling.
I think you made the same mistake again (Bearcat vs Bearhawk). I'd love to see this Bearcat with a Rotax :)

Anyway, here is a Bearhawk with an IO-540:

https://www.youtube.com/watch?v=UC5iFwn6ExA
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CpnCrunch
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Re: MERGED power curve / floats posts

Post by CpnCrunch »

aeroncasuperchief wrote: Mon Nov 19, 2018 6:30 pm WHERE did I say I used GS as a reference for BS approaches? Or that I claimed they are stable? I will eat those foolish statements If I had written them !

I call bullshit on YOU !
Back side of the power curve approaches should be pretty stable, unlike flying straight and level in slow flight.

https://www.youtube.com/watch?v=eDUfr-EQqEM
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aeroncasuperchief
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Re: MERGED power curve / floats posts

Post by aeroncasuperchief »

20180628_151855.jpg
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This is the A/C I assembled and test flew for a customer. Nice performer, 1200 FPM through 8500 feet with 2 people and full mains !
With an MGL iEFIS, A/P Etc, it has all you want for those Idaho strips less the Alaska tires of course
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