Results 1 to 32 of 32

Thread: Stall or turbulence

  1. #1
    S2D's Avatar
    Join Date
    May 2002
    Location
    Montana
    Posts
    4,060
    Post Thanks / Like

    Stall or turbulence

    The thread showing the guy stall his airplane at a landing contest and subsequent start of a spin got me to thinking (yea I know Thats dangerous)

    Suppose you are doing the typical too low and too slow moose observation circle and suddenly your left wing and nose starts to drop.

    How do you instantly know it is a stall and not wake turbulence, and do you react the same to both situations.
    I may be wrong but that probably won't stop me from arguing about it.
    Thanks 40m thanked for this post

  2. #2

    Join Date
    Nov 2012
    Location
    Lake Lanier, GA
    Posts
    1,072
    Post Thanks / Like
    The new training for "upset recovery" the FAA is pushing is "Push, roll, power". It is considered simple, immediate and easily executed. While I am not too excited about going lower for wake turbulence, pull up is often a quicker and safer path, I understand the need to develop a simple and easily executed procedure for all LOC situations. The basic idea is to unload the airplane to a 0.5g condition that makes the wing and controls more effective and in that respect, "push" is a good plan and it works for all attitudes even inverted. Roll is get the horizon and roll the shortest way. Power either retard or add power as needed to stabilize the aircraft. We sent out a bunch of guys to fly in an Extra 300 and the aircraft was put in every conceivable upset situations including inverted flight and push, roll, power recovered every time. As I said it is not the end all to be all but it is a pretty good plan when you are startled by LOC.

  3. #3
    Gordon Misch's Avatar
    Join Date
    Dec 2003
    Location
    Toledo, Wa (KTDO)
    Posts
    3,358
    Post Thanks / Like
    I don't understand how "push" would be desirable in a descending spiral or inverted? Maybe "neutralize"?
    Gordon

    N4328M KTDO
    My SPOT: tinyurl.com/N4328M (case sensitive)

  4. #4

    Join Date
    Dec 2008
    Location
    Nova Scotia
    Posts
    891
    Post Thanks / Like
    As a student I took off too close behind a Beaver at a small airstrip. Another time around 5,000 hours I succumbed to an incipient moose stall---passenger was filming nine moose together on a tiny peninsula, wing going down, limp stick. Both times I could only remember the line in Stick and Rudder: when in trouble reduce AOA. Worked for me.
    Thanks OLDCROWE thanked for this post
    Likes skywagon8a, Cubus Maximus, cruiser liked this post

  5. #5

    Join Date
    Nov 2012
    Location
    Lake Lanier, GA
    Posts
    1,072
    Post Thanks / Like
    Quote Originally Posted by Gordon Misch View Post
    I don't understand how "push" would be desirable in a descending spiral or inverted? Maybe "neutralize"?
    Inverted you want to push, to keep the nose dropping through the horizon. In a tight spiral, pushing will unload the airplane and prevent tightening the spiral. With the airplane unload the controls are more effective to roll out.

  6. #6
    Gordon Misch's Avatar
    Join Date
    Dec 2003
    Location
    Toledo, Wa (KTDO)
    Posts
    3,358
    Post Thanks / Like
    Pushing while inverted will raise the nose, not "keep it dropping through the horizon". Unless pushing enough to stall it, I guess! To unload, just neutralize pitch inputs??


    Aerobatics guys??
    Gordon

    N4328M KTDO
    My SPOT: tinyurl.com/N4328M (case sensitive)
    Thanks cubnut thanked for this post

  7. #7
    mvivion's Avatar
    Join Date
    Jun 2003
    Location
    Bozeman,MT
    Posts
    10,461
    Post Thanks / Like
    Pushing while inverted will increase AOA and worsen your situation.....the wrong response, and you only get one shot at this. The appropriate response is "elevator through neutral", as taught by Rich Stowell. Regardless of whether you're inverted or upright, that will reduce AOA.

    I think the biggest issue with the so called "moose stall", and the most difficult to simulate in training, is the surprise. There is all kinds of documentation of how long it takes to respond to a true surprise. Firearms training faces the same issue. Stand out there at a range with a pistol holstered, waiting for a target to face is a whole different situation than while you're checking someone's fishing license, he pulls out a pistol and starts shooting.

    About the only thing we can do is, as GeeBee suggests, develop a basic set of procedures to perform any time an unusual attitude occurs. So, yes, "Pitch, roll, power" works, but the pitch has to represent stick through neutral, not "push".

    Now, understand that in most standard category aircraft, the likelihood of getting upside down is pretty low, but in aerobatics, it's actually a lot higher.

    I highly recommend Rich's books and videos, especially, "Emergency Maneuver Training". I also highly recommend flying with Rich if you have the opportunity. He is the "Spin Master" after all. He's done more looking into the "moose stall" and developed procedures to use in the event you get there than anyone I know of. His web site is: http://www.richstowell.com/

    MTV
    Likes Gordon Misch liked this post

  8. #8
    S2D's Avatar
    Join Date
    May 2002
    Location
    Montana
    Posts
    4,060
    Post Thanks / Like
    Quote Originally Posted by mvivion View Post



    I highly recommend Rich's books and videos, especially, "Emergency Maneuver Training". I also highly recommend flying with Rich if you have the opportunity. He is the "Spin Master" after all. He's done more looking into the "moose stall" and developed procedures to use in the event you get there than anyone I know of. His web site is: http://www.richstowell.com/

    MTV
    After 30 years providing spin, EMT, and aerobatic instruction on a regular basis, Rich has decided to take a sabbatical from daily flight training to work on other aviation projects. If you are looking to contact us on another matter, please use the standard contact form.

    I may be wrong but that probably won't stop me from arguing about it.

  9. #9

    Join Date
    Nov 2012
    Location
    Lake Lanier, GA
    Posts
    1,072
    Post Thanks / Like
    Nope, I've rolled several transport category aircraft in the simulator and unless you are full stick forward you will fall out very quickly with a resulting acceleration that would be unsurvivable. Most aerobatic aircraft can go stick neutral because of their airfoil, but I've also rolled some standard category aircraft, (being young and stupid) that require significant stick forward, so "push" is a good move for the non aerobatic pilot who finds himself inverted.
    These are the guys I flew with and I think the video and web page make for a good read

    https://www.youtube.com/watch?v=y1TUJprbEuA

    https://apstraining.com/unusual-attitude-recovery/
    Thanks Gordon Misch, super stol thanked for this post

  10. #10

    Join Date
    Sep 2002
    Location
    Southern NH
    Posts
    478
    Post Thanks / Like
    We were taught push as well (at FlightSafety in the sim), as the instinct for most pilots is to pull to get away from the ground. Pulling when inverted is what they were trying to discourage.
    Mark
    Thanks Gordon Misch thanked for this post

  11. #11
    aktango58's Avatar
    Join Date
    Aug 2004
    Location
    18AA
    Posts
    9,084
    Post Thanks / Like
    Quote Originally Posted by S2D View Post
    The thread showing the guy stall his airplane at a landing contest and subsequent start of a spin got me to thinking (yea I know Thats dangerous)

    Suppose you are doing the typical too low and too slow moose observation circle and suddenly your left wing and nose starts to drop.

    How do you instantly know it is a stall and not wake turbulence, and do you react the same to both situations.
    Back to the original question as I have no idea on inverted as I work hard to stay upright, (even walking), It does not matter if it is a stall, or wake turbulence, because if it is the dreaded WT it will induce a stall anyway if you are really on edge.

    Since both result in the same situation, (full pucker of all major orifices) STALL, the reaction should be the same- push both hands forward fast and stand on the uphill rudder.

    If you are anywhere close to a moose stall situation, a good GUMP check getting into your observation mode should be done to prevent 'popping' a tank or other 'fun' happenings, and your hands should be on the throttle and stick... so both forward gives power and relaxes the elevator, and at the same time your rudder can be applied with your foot.
    I don't know where you've been me lad, but I see you won first Prize!
    Thanks S2D, Bowie thanked for this post
    Likes super stol liked this post

  12. #12
    Gordon Misch's Avatar
    Join Date
    Dec 2003
    Location
    Toledo, Wa (KTDO)
    Posts
    3,358
    Post Thanks / Like
    From the APS website:
    PUSH: This means, “unload” the aircraft. If you were pulling back on the yoke, now is the time to stop! It does not mean an aggressive negative-G push to keep the nose up. The idea is merely to decrease or possibly halt the nose’s trend downward while the aircraft is being rolled upright.
    https://apstraining.com/unusual-attitude-recovery/
    Gordon

    N4328M KTDO
    My SPOT: tinyurl.com/N4328M (case sensitive)
    Likes kestrel liked this post

  13. #13
    PerryB's Avatar
    Join Date
    Aug 2007
    Location
    Northern Calif.
    Posts
    1,810
    Post Thanks / Like
    "Roll" is another area that needs attention. A LOT of pilots will react to the dropping wing with the ailerons (very understandable) but as we all know, going very far with the stick is only going to get you deeper in the doo. The thing that concerns me is that a lot of the newer crop of instructors teach spin avoidance (not bad, unto itself) but not any true recovery. At the first burble they have you pushing it over and flying again. Rudder skills seem to be waning these days. Jeez, listen to me...
    After Monday and Tuesday, even the calendar says WTF !
    Thanks S2D, super stol thanked for this post

  14. #14
    Gordon Misch's Avatar
    Join Date
    Dec 2003
    Location
    Toledo, Wa (KTDO)
    Posts
    3,358
    Post Thanks / Like
    Right on, Perry. I did quite a few spins in my primary training. Then kept doing them for fun. Saved my bacon once when turning too tight, cuz the correction was reflexive. Thanks Steve Hewitt (my primary instructor).
    Gordon

    N4328M KTDO
    My SPOT: tinyurl.com/N4328M (case sensitive)

  15. #15

    Join Date
    Sep 2003
    Posts
    6,760
    Post Thanks / Like
    Speaking of mis-using ailerons: I see a lot of otherwise well qualified pilots steering with them while landing. It takes me literally dozens of hours to get the aileron into the wind, and dozens of hours spraying dope on wingtips when they forget.

    Nobody teaches this any more. But the Feds are demanding stabilized approaches in J-3 Cubs on checkrides.

    The original stall with wing drop: anybody know if that aircraft had VGs? My Cubs do not drop a wing in straight ahead stalled flight.
    Likes JP liked this post

  16. #16
    JP's Avatar
    Join Date
    Mar 2003
    Location
    The Big Woods of Maine
    Posts
    3,201
    Post Thanks / Like
    Unload (usually an affirmative push) and simultaneously step on the sky (with the appropriate rudder pedal). Roll via the stick isn't going to cut it on a stock cub wing once said wing is stalled. No flow, no go.

    Sent from my [device_name] using SuperCub.Org mobile app
    JP Russell--The Cub Therapist
    1947 PA-11 Cub Special
    www.bloomerrussellbeaupain.com

  17. #17
    Cub Special Ed's Avatar
    Join Date
    Oct 2016
    Location
    MT/SD
    Posts
    440
    Post Thanks / Like
    Not recomended in an early husky. I know a guy who survived the exact situation while working low level. In the early huskies, they pitch nose straight down at the ground in your own wake. This situation was level and through the last pass. Just said tail came up and he was looking straight at the ground. Stick full frwrd, full power, then stick back before impact. Broke the crews backs and panckaked the huskie. I believe theres a pic foating around on the internet somewhere. This exact charectoristic is why aphis and border patrol no longer uses them.
    "There are 3 kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." Will Rogers
    Likes JP liked this post

  18. #18
    mvivion's Avatar
    Join Date
    Jun 2003
    Location
    Bozeman,MT
    Posts
    10,461
    Post Thanks / Like
    Quote Originally Posted by Cub Special Ed View Post
    Not recomended in an early husky. I know a guy who survived the exact situation while working low level. In the early huskies, they pitch nose straight down at the ground in your own wake. This situation was level and through the last pass. Just said tail came up and he was looking straight at the ground. Stick full frwrd, full power, then stick back before impact. Broke the crews backs and panckaked the huskie. I believe theres a pic foating around on the internet somewhere. This exact charectoristic is why aphis and border patrol no longer uses them.
    That “characteristic” evaded me in a few thousand hours of working Huskys at low level. And I’ve tried many times to demonstrate it. I’ve flown the airplane very aggressively trying to get it to depart, with never a hint of the tail departing in a stall. I’ve also flown with and discussed this with the two test pilots who were able to reproduce this “characteristic”, but they had to go through some significant machinations to get there, like use two airplanes, in VERY aggressive maneuvering.

    The Husky accidents I’ve seen discussed were clearly “standard” stall/spin accidents. In one case I know of the Pilot was killed, but the passenger survived. Looking at that wreckage, it’s hard to believe anyone survived. But that was clearly a stall/spin, with rotation at impact.

    FWIW.

    MTV
    Last edited by mvivion; 02-09-2018 at 08:33 AM.
    Likes JP liked this post

  19. #19
    S2D's Avatar
    Join Date
    May 2002
    Location
    Montana
    Posts
    4,060
    Post Thanks / Like
    Suppose you are at the critical angle of attack when you hit the wake turbulence. Wouldn't aileron input to correct for the roll cause the down wing to stall further aggravating the problem?
    On the other hand wouldn't rudder input to the skyward wing cause that wing to slow down stalling it and start a spin that way?

    Obviously unloading the wing should be the first reflex, but in wake turbulence are things always as they should be?
    Last edited by S2D; 02-10-2018 at 10:18 PM.
    I may be wrong but that probably won't stop me from arguing about it.
    Likes JP liked this post

  20. #20

    Join Date
    Nov 2012
    Location
    Lake Lanier, GA
    Posts
    1,072
    Post Thanks / Like
    In "roll" if you read what is written they say, "use the rudder" but use it judiciously. Especially on transport airplanes. But even FAR 23 Normal category can not accept a lot of rudder abuse during a time of stall. I found that out when I had my head up my butt with a student doing approach to landing stalls in an AA-1A. Besides saying "NO SPINS" with a big red placard I found out when you do inadvertently enter a spin, you can damage the stab getting it out.

    Look guys, this procedure is the "oh s***" procedure. It is designed for survival not conscious aviating. It is like the "land straight ahead" when the engine fails. You and I both know we can make it back to the runway at 500' with skill. Will that skill be there when you are surprised? When the proverbial excrement hits the fan, often times you have to go to survival mode and that is what this procedure represents. Is it the perfect way to exit a spin? No. Will it get you out of one? Yes. That was the point of this OP here. What to do when you don't know what to do or what happened.
    Likes mam90, JP, kestrel liked this post

  21. #21
    Cub Special Ed's Avatar
    Join Date
    Oct 2016
    Location
    MT/SD
    Posts
    440
    Post Thanks / Like
    Quote Originally Posted by mvivion View Post
    That “characteristic” evaded me in a few thousand hours of working Huskys at low level. And I’ve tried many times to demonstrate it. I’ve flown the airplane very aggressively trying to get it to depart, with never a hint of the tail departing in a stall. I’ve also flown with and discussed this with the two test pilots who were able to reproduce this “characteristic”, but they had to go through some significant machinations to get there, like use two airplanes, in VERY aggressive maneuvering.

    The Husky accidents I’ve seen discussed were clearly “standard” stall/spin accidents. In one case I know of the Pilot was killed, but the passenger survived. Looking at that wreckage, it’s hard to believe anyone survived. But that was clearly a stall/spin, with rotation at impact.

    FWIW.

    MTV
    Funny, the guy i know said "ive got thousands of husky hours and never had a problem". Right up until he did. He said the only reason he survived was hanger talk he'd heard about the matter.
    "There are 3 kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." Will Rogers
    Likes JP liked this post

  22. #22
    mvivion's Avatar
    Join Date
    Jun 2003
    Location
    Bozeman,MT
    Posts
    10,461
    Post Thanks / Like
    Quote Originally Posted by Cub Special Ed View Post
    Funny, the guy i know said "ive got thousands of husky hours and never had a problem". Right up until he did. He said the only reason he survived was hanger talk he'd heard about the matter.
    Yeah, there's a lot of he said/she said in the aviation world......much of it BS. Count the number of folks who've died in Super Cubs over the years in similar circumstances. Bottom line is you've got to fly the airplane, whatever flavor of airplane you choose to fly.

    MTV
    Likes mam90, cubdriver2, JP, phdigger123, kestrel liked this post

  23. #23
    Cub Special Ed's Avatar
    Join Date
    Oct 2016
    Location
    MT/SD
    Posts
    440
    Post Thanks / Like
    This story came directly from the pilot. It was after level off and dropping in to point of intrest. Kind of like ghosts. Ive never seen one but im not going to say they dont exist. I completly agree. Fly de plane.
    "There are 3 kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." Will Rogers
    Likes JP liked this post

  24. #24
    S2D's Avatar
    Join Date
    May 2002
    Location
    Montana
    Posts
    4,060
    Post Thanks / Like
    Quote Originally Posted by Cub Special Ed View Post
    In the early huskies, they pitch nose straight down at the ground in your own wake. This situation was level and through the last pass. Just said tail came up and he was looking straight at the ground. Stick full frwrd, full power, then stick back before impact.

    since the tail is supposedly a wing with down lift ( or is it just a wind deflector) couldn't a properly placed downdraft ( wake turbulence) stall the tail causing it to pitch up dramatically. especially if the elevators were deflected upward and you stalled the wing at the same time ?

    I'm getting way above my aerodynamics education level !!!
    I may be wrong but that probably won't stop me from arguing about it.
    Thanks Cub Special Ed thanked for this post

  25. #25
    BC12D-4-85's Avatar
    Join Date
    Feb 2016
    Location
    Fairbanks, AK.
    Posts
    1,622
    Post Thanks / Like
    Large flaps and/or a sideways flying fuselage have a way of sometimes disturbing flow and down pressure over the tail too.

    Gary
    Thanks Cub Special Ed thanked for this post

  26. #26
    Cub Special Ed's Avatar
    Join Date
    Oct 2016
    Location
    MT/SD
    Posts
    440
    Post Thanks / Like
    And wouldnt an O-360 with constant speed prop make it more nose heavy exacerbating the issue on those a-model huskies?
    "There are 3 kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." Will Rogers
    Thanks windy thanked for this post

  27. #27
    Cub Special Ed's Avatar
    Join Date
    Oct 2016
    Location
    MT/SD
    Posts
    440
    Post Thanks / Like
    And could be that the reason some a1-a drivers have never experienced it is becous mabe it takes certain air qualities. Like mabe a no wind day with a temp inversion which could cause the wake to hang in the same spot longer?
    "There are 3 kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." Will Rogers
    Likes courierguy liked this post

  28. #28
    G44's Avatar
    Join Date
    Oct 2011
    Location
    SW Michigan
    Posts
    458
    Post Thanks / Like
    Quote Originally Posted by Cub Special Ed View Post
    And wouldnt an O-360 with constant speed prop make it more nose heavy exacerbating the issue on those a-model huskies?
    No, not necessarily. CG is CG.
    Likes kestrel, DENNY liked this post

  29. #29
    G44's Avatar
    Join Date
    Oct 2011
    Location
    SW Michigan
    Posts
    458
    Post Thanks / Like
    Quote Originally Posted by Cub Special Ed View Post
    And could be that the reason some a1-a drivers have never experienced it is becous mabe it takes certain air qualities. Like mabe a no wind day with a temp inversion which could cause the wake to hang in the same spot longer?
    It would happen in a Super Cub, Scout or any other airplane for that matter. Dirty air low to the ground can be dangerous in ANY airplane, not just Husky's.
    Likes kestrel liked this post

  30. #30
    kestrel's Avatar
    Join Date
    Aug 2013
    Location
    Southern NH
    Posts
    304
    Post Thanks / Like
    One must be careful how they interpret cherry picked anecdotes...

    Sent from my [device_name] using SuperCub.Org mobile app
    --
    Bearhawk, RV-4

  31. #31
    WhiskeyMike's Avatar
    Join Date
    Jun 2003
    Location
    West Boxford MA
    Posts
    880
    Post Thanks / Like
    What is all this horse doo-doo about "early Huskies?" The later the model, the heavier. No different than a Super Cub at the same loaded weight. Maybe a different feel due to the fixed stabilizer. An early Husky is a lighter Husky. And by the way, it has more flap than a PA-18 while employing the same airfoil. You can make the same mistake in either airplane with the same result. Let's nor blame the airplanes. I kept away from Super Cubskys for years based on that urban myth, then I bought one. After all, imitation is the sincerest form of flattery and the Husky is based on the PA-18 as are all of the copies of the original 18. Carbon this, Dakota that, Airframes, Smith, SQ 123. You name it. We all love the Super Cub, and use various versions for various reasons. For me the Cubsky fits the mission: 50 gallons fuel, fast cross country, 180 HP, long prop (not the original of course) Cleveland wheels (lots of my old 18's had expander tubes) No strut fork issues, and a less shaky tail when towing. (even the Cubsky has tail issues.) Nothing is perfect, nothing is for free, and as for stall spin, you pays your money and you takes your choice. As they used to tell me...learn and live.
    Thanks L18C-95 thanked for this post
    Likes kestrel liked this post

  32. #32
    S2D's Avatar
    Join Date
    May 2002
    Location
    Montana
    Posts
    4,060
    Post Thanks / Like
    Quote Originally Posted by WhiskeyMike View Post
    What is all this horse doo-doo about "early Huskies?" The later the model, the heavier. No different than a Super Cub at the same loaded weight. Maybe a different feel due to the fixed stabilizer. An early Husky is a lighter Husky. And by the way, it has more flap than a PA-18 while employing the same airfoil. You can make the same mistake in either airplane with the same result. Let's nor blame the airplanes. I kept away from Super Cubskys for years based on that urban myth, then I bought one. After all, imitation is the sincerest form of flattery and the Husky is based on the PA-18 as are all of the copies of the original 18. Carbon this, Dakota that, Airframes, Smith, SQ 123. You name it. We all love the Super Cub, and use various versions for various reasons. For me the Cubsky fits the mission: 50 gallons fuel, fast cross country, 180 HP, long prop (not the original of course) Cleveland wheels (lots of my old 18's had expander tubes) No strut fork issues, and a less shaky tail when towing. (even the Cubsky has tail issues.) Nothing is perfect, nothing is for free, and as for stall spin, you pays your money and you takes your choice. As they used to tell me...learn and live.
    What do you use you 'cubsky' for?

    Sent from my E6810 using Tapatalk
    I may be wrong but that probably won't stop me from arguing about it.

Similar Threads

  1. Wake Turbulence, The Movie
    By stewartb in forum The Art and Science of Flying
    Replies: 7
    Last Post: 10-07-2016, 05:15 AM
  2. Stall Horn to Stall Light
    By banner tow pilot in forum Take Action Jackson
    Replies: 24
    Last Post: 11-25-2008, 11:45 PM
  3. Flying in Turbulence...What can you do to be safer?
    By cubflier in forum Tips and Tricks
    Replies: 4
    Last Post: 02-27-2007, 06:21 PM

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •