Stall/spin and ground reference maneuvers

Kirk,

Thanks for your detailed answer. I understand what you're saying - be flexible and be prepared to do what you gotta do when you gotta do it.

I tend to make mistakes when I rush, so I try to keep ahead of the situation. During landings I do this by using the typical downwind-base-final pattern. It doesn't always work out, of course, during BFRs it's common for me to get a release on tow and hear the instructor say "where you going to land now"? That practice has helped immensely with the problems you mentioned of being in a gaggle of gliders all trying to land now, or needing to make a quick change of farmers field when the first choice had to be ruled out.

-John, Q3

On Wednesday, March 5, 2014 11:03:59 PM UTC-5, kirk.stant wrote:
On Wednesday, March 5, 2014 12:08:55 PM UTC-6, John Carlyle wrote:
Thank for writing that - very interesting that you mix approach types.

My experience is that you can never be sure that you will be able to fly a "textbook" pattern, so better to be comfortable in a variety of situations. It's a matter of getting your glider from where it is to short final to your desired landing area, at a safe speed and altitude for the existing conditions. Patterns are guides - but one can land safely from all sorts of patterns; one can also (as we are proving) crash from "textbook" patterns.

I'm not too clear about your comment "always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting". I always use a downwind-base-final pattern, I've logged 10 landouts in farmers fields, and except for having to dodge an electric wire fence once they were low or no drama events (although some of the retrieves were interesting).

If you have the luxury of large fields and plenty of time, then setting up a "standard" pattern is always a good option - but what if you don't have those options? You may find on base that the field you picked is not landable, or the wind changes 180 degrees due to a gust front; you may be following a valley and have to suddenly land in that field on your left; or you may get back to your own field and be in a gaggle of gliders all vying for the same runway at the same time. Most of my landouts have been benign also - but I've also done a couple of final glides into fields that I couldn't see and the pattern consisted of one turn, gear & flaps down, and land. I think you have to be prepared for these kinds of eventualities, and be able to fly your glider safely when low and stressed. That takes planning and practice.

Your "de-stabilized" (non-constant airspeed) approach comment was also interesting. I tend to keep high until on final, just to keep my options open, but my speed stays pretty much constant. Being high has helped me on several occasions to delay a bit (once a person behind me with no radio landed under me, another time someone drove onto the field). Do I understand correctly that you tend to keep your energy in speed rather than altitude?

Energy is the key, high and fast is nice, lower and fast is OK, but slow and low is never good until over the threshold! I see my "hot" pattern speed as a minimum and if it gets a bit high I don't worry about it - final is a fine time to decelerate and get ready to land. Again, it depends on the situation - if there are lots of gliders around trying to land, then playing off altitude and speed is a useful tool to use to get sequenced into the flow - and extra speed on final is good unless you KNOW you have to land short! If there is nothing going on and it's the last landing of the day, then a perfect, constant speed pattern is a fun challenge; but if it's a hectic arrival, I may have to maneuver aggressively to get down; then speed control is more of the "stay fast, stay fast, stay fast..." variety until the immediate problem of where to go is solved. Stall/spins make lousy pattern entries!

Cheers,
Kirk
66

On 3/7/2014 8:24 AM, John Carlyle wrote:
Bob,

I've never experienced vertigo during flight (only on the ground from
illness or alcohol issues), so I'm happy to admit I was wrong by a factor
of 10 in estimating its onset. Can we settle on a vertigo onset of 5-10
seconds for sake of argument?

John - I'm 'happy to settle on any time-interval anyone would like' for
vertigo onset, because - as I've no doubt you well realize - what really
matters is that it WILL happen, and if Joe Pilot doesn't already have a
well-rehearsed Plan B ready for PDQ implementation, he's just transitioned
from a "Crud!" or "Oh s**t!" situation to a deadly one.

Getting back to the original topic, there we are, in our base to final turn
with our ASI reading yellow diamond value plus half the wind speed. Suppose
we shift our gaze from over the nose (where we were looking at pitch, yaw
string and bank angle) towards the inside wing (to check that the airport
hasn't run away). In our peripheral vision we see some unusual motion of
the wing. We can either ignore it and keep on flying the plane, or we can
focus on it. If we ignore it, no problem, but if we focus on it there are
four possibilities as to what can happen next.

First case, we tell ourselves "that's interesting, but I've got a plane to
fly", we shift our gaze back to the nose, keep the turn coordinated and
successfully land. Second case, we tell ourselves "that's interesting, I've
never seen anything like that, I wonder why that's happening, doesn't
matter now, I've got a plane to fly", we shift our gaze back to the nose,
keep the turn coordinated and successfully land. Third case, we tell
ourselves "that's interesting, I've never seen anything like that, I wonder
why that's happening, hmmm, maybe I should put in some more rudder", and we
don't land successfully. Fourth case, we tell ourselves "that's
interesting, I've never seen anything like that, I wonder why that's
happening, hmmm, wow those trees are close and they're really moving funny,
I'm going to have to remember this to tell the guys all about it, I wonder
if I bleed off too much altitude, hey there's a good looking lady down
there, wonder if she sees me up here, whoops, I'm dizzy and don't feel too
good, gee those trees are really close and now they're spinning around and
around, oh I'm sick" and we don't land successfully.

In the first two cases, there's no problem. I think we can agree case four
is very, very unlikely, as no one is likely to fixate on something unusual
for so long (5-10 seconds) when they're low that they'll succumb to vertigo
and crash. It's drummed into us as students that above all else, we need to
fly the plane, no matter what.

But what about case three? Some in this thread have said it's possible, and
that one needs ground reference training to become familiar with the
reverse wing tip movement sensation so you don't try to "correct it".
Maybe, but I'd argue no. First, you're going to have to quit doing
something very important (maintaining a coordinated turn while low) to
focus on something secondary in order to realize what's happening. Next
you're going to have to "do something" impulsively without cross-checking
with a quick gaze at your yaw string that something really needs to be done
to maintain your coordinated turn. If you're the sort that would be
susceptible to these actions, I'd suggest there's training in other areas
that needs to be accomplished first before you consider ground reference
training.

I don't fundamentally disagree with your assessments one bit. The trick for an
instructor (or Joe Pilot, for that matter, if J.P. is vaguely insightful) is
to decide if Joe Pilot is in fact susceptible to life-threatening
distractions. I pretty quickly in my 'pilot career' concluded I was not (or
for darned sure intended to make certain I didn't fall prey to that stupid
trap), and my motivation was the dead pilots whom I suspected WERE for some
reason or other. In either case, additional training on SOMEthing related to
'how to properly fly a (definitionally non-standard) pattern' seems in order. :-)


Now, let me follow your topic drift. Suppose it takes 5-10 seconds without
outside orientation references for vertigo to set in. Why wouldn't all the
passengers in the center section of a widebody at night get nauseous? If
your answer is "they use the cabin as an orientation reference for their
inner ear", then why can't the pilot use his cockpit features for the same
purpose? He'll probably still lose control of the aircraft, but he
shouldn't become nauseous.

Indeed...

For the record, I've not yet experienced nausea with my vertigo incidents
(in-glider, on-ground, in FAA 'IFR chair', etc.). In any event, small comfort
hitting the ground comfortably and out of control as opposed to queasily and
out of control, eh? ;-)

Bob W.

On Friday, March 7, 2014 9:24:21 AM UTC-6, John Carlyle wrote:
But what about case three? Some in this thread have said it's possible, and that one needs ground reference training to become familiar with the reverse wing tip movement sensation so you don't try to "correct it". Maybe, but I'd argue no. First, you're going to have to quit doing something very important (maintaining a coordinated turn while low) to focus on something secondary in order to realize what's happening. Next you're going to have to "do something" impulsively without cross-checking with a quick gaze at your yaw string that something really needs to be done to maintain your coordinated turn. If you're the sort that would be susceptible to these actions, I'd suggest there's training in other areas that needs to be accomplished first before you consider ground reference training.

I don't understand why the motion of the wingtip over the ground is such a big deal? Who looks (focuses) at their wingtip in flight? I'm looking way beyond it at some other object - who cares what my wingtip is doing? In a steady turn, once established, it would take a lot of rudder to significantly move the nose and create dangerous yaw - who boots the rudder while in a steady turn? I think there is something more basic going on here - poor/lazy airmanship! Get out and fly more; practice stalls/departures/spiral dive recoveries, be aggressive in your pattern - fly down to the flare (fast, steep, in control), instead of being scared to get close to the ground, etc....

Now, let me follow your topic drift. Suppose it takes 5-10 seconds without outside orientation references for vertigo to set in. Why wouldn't all the passengers in the center section of a widebody at night get nauseous? If your answer is "they use the cabin as an orientation reference for their inner ear", then why can't the pilot use his cockpit features for the same purpose? He'll probably still lose control of the aircraft, but he shouldn't become nauseous.

Because the airliner is always in coordinated flight and the turn/roll rates as very slow. Trust me, every passenger in an airliner doing turns in clouds or at night has vertigo, but since they are unaware of it, unless they are looking out the window when they pop out of a cloud in a turn they will not become aware of it or get nausious. Next time you fly commercial, focus your gaze forward down the cabin during the takeoff acceleration, and you will sense the plane pitching up significantly BEFORE rotation (acceleration effect on inner ear - vertigo), then look out the window and note how fast your equilibrium reestablishes. This really was fun in something like a C-130 or C-141 with no windows and good acceleration, it felt like you pitched up 10 degrees immediately!

Kirk
66

On Friday, March 7, 2014 7:47:33 AM UTC-8, John Carlyle wrote:
Kirk,



Thanks for your detailed answer. I understand what you're saying - be flexible and be prepared to do what you gotta do when you gotta do it.



I tend to make mistakes when I rush, so I try to keep ahead of the situation. During landings I do this by using the typical downwind-base-final pattern. It doesn't always work out, of course, during BFRs it's common for me to get a release on tow and hear the instructor say "where you going to land now"? That practice has helped immensely with the problems you mentioned of being in a gaggle of gliders all trying to land now, or needing to make a quick change of farmers field when the first choice had to be ruled out.



-John, Q3



On Wednesday, March 5, 2014 11:03:59 PM UTC-5, kirk.stant wrote:

On Wednesday, March 5, 2014 12:08:55 PM UTC-6, John Carlyle wrote:

Thank for writing that - very interesting that you mix approach types..



My experience is that you can never be sure that you will be able to fly a "textbook" pattern, so better to be comfortable in a variety of situations. It's a matter of getting your glider from where it is to short final to your desired landing area, at a safe speed and altitude for the existing conditions. Patterns are guides - but one can land safely from all sorts of patterns; one can also (as we are proving) crash from "textbook" patterns..



I'm not too clear about your comment "always flying the same pattern into the same airfield pretty much guarantees that your first landout will be exciting". I always use a downwind-base-final pattern, I've logged 10 landouts in farmers fields, and except for having to dodge an electric wire fence once they were low or no drama events (although some of the retrieves were interesting).



If you have the luxury of large fields and plenty of time, then setting up a "standard" pattern is always a good option - but what if you don't have those options? You may find on base that the field you picked is not landable, or the wind changes 180 degrees due to a gust front; you may be following a valley and have to suddenly land in that field on your left; or you may get back to your own field and be in a gaggle of gliders all vying for the same runway at the same time. Most of my landouts have been benign also - but I've also done a couple of final glides into fields that I couldn't see and the pattern consisted of one turn, gear & flaps down, and land. I think you have to be prepared for these kinds of eventualities, and be able to fly your glider safely when low and stressed. That takes planning and practice.



Your "de-stabilized" (non-constant airspeed) approach comment was also interesting. I tend to keep high until on final, just to keep my options open, but my speed stays pretty much constant. Being high has helped me on several occasions to delay a bit (once a person behind me with no radio landed under me, another time someone drove onto the field). Do I understand correctly that you tend to keep your energy in speed rather than altitude?



Energy is the key, high and fast is nice, lower and fast is OK, but slow and low is never good until over the threshold! I see my "hot" pattern speed as a minimum and if it gets a bit high I don't worry about it - final is a fine time to decelerate and get ready to land. Again, it depends on the situation - if there are lots of gliders around trying to land, then playing off altitude and speed is a useful tool to use to get sequenced into the flow - and extra speed on final is good unless you KNOW you have to land short! If there is nothing going on and it's the last landing of the day, then a perfect, constant speed pattern is a fun challenge; but if it's a hectic arrival, I may have to maneuver aggressively to get down; then speed control is more of the "stay fast, stay fast, stay fast..." variety until the immediate problem of where to go is solved. Stall/spins make lousy pattern entries!



Cheers,

Kirk

66

Last Saturday - on downwind - have called pattern on radio - getting ready to turn base (squared off pattern), when I notice tow plane has maybe decided I was just kidding about landing, and touches down on runway - bless his heart - or maybe didn't hear my radio calls. Start turn to base, watching yaw string and speed and runway and tow. I know the ground is still there, but I have to know how cluttered or clear it is. I'm on TLAR so altimeter doesn't really matter at this point. Just know I can still land long or short, but have to decide pretty quickly which, unless tow clears runway. There are three gliders staged on left third of runway (we have a wide dirt runway), and tow is taxiing toward them on right side of runway, so runway is now blocked and my original aim point is meaningless - would hit tow, and if I try to miss tow by going left, I'll hit the staged gliders. If I go right of tow, I'm into the desert and a severely damaged glider. As I turn final, I keep altitude and air speed for either landing short or landing way, way long. Don't like either option, since that's a long push to my trailer, but I gotta fly the glider and be safe - a long push to trailer is better than the other options at this point. Since it's a gusty day, need extra airspeed anyway. Tow is now about even with staged gliders, runway is totally blocked, and I have run out of time. Since it's a gusty day, I don't want to chance getting knocked down (wind shear) trying to land long by flying over everyone, so opt for short and deploy full air brakes and get ready to start a slip since I'm planning on touching down about 400' - 500' shorter than original plan. Still watching airspeed, since I don't want to land short and still end up rolling into the ground gaggle because of too much ground speed. About 1 second later, tow pulls in front of gliders, clearing the right side of the runway, so I go back to original plan. In come the brakes, up comes the nose a bit and I touch down as originally planned. What wingtips? Never saw them. What was I focused on? Just about everything I thought was important, but primarily on landing safely.
Eric Bick

Just curious, why didn't you try to communicate with the tug again? When I have a communication problem I first assume,
1. My call out got stepped on
2. My radio volume is turned down, I turn it up immediately to 3/4
3. My radio is out of service
Pressing the transmit button and transmitting your intentions and asking the tugs intentions, again, and maybe asking for a radio check if in doubt, only takes a moment.
There may have been others in the pattern, trying to communicate with you.
If I flew into a pattern thinking my radio was transmitting and then I found out it wasn't, it would make my hair stand on end.
no offense, just saying.

On Monday, March 10, 2014 8:11:25 PM UTC-7, Nick Kennedy wrote:
Just curious, why didn't you try to communicate with the tug again? When I have a communication problem I first assume,

1. My call out got stepped on

2. My radio volume is turned down, I turn it up immediately to 3/4

3. My radio is out of service

Pressing the transmit button and transmitting your intentions and asking the tugs intentions, again, and maybe asking for a radio check if in doubt, only takes a moment.

There may have been others in the pattern, trying to communicate with you.

If I flew into a pattern thinking my radio was transmitting and then I found out it wasn't, it would make my hair stand on end.

no offense, just saying.

No offense taken. There's a lot more to this story than I put in the post, and it's been a topic of discussion at our field more than once.