Are 'Single 180 Turn From Downwind to Final' and 'Stall-spin on Turnfrom Base to Final' mutually exclusive?

On Sunday, July 31, 2016 at 10:32:02 PM UTC-4, Dan Marotta wrote:

Fly what works for you and don't disparage techniques that are out
of your sphere of experience.

....pop quiz then.

You're #3 in the pattern behind a student in a 1-34 flying a standard glider pattern and a tow plane. Behind you is another student + CFI in an L-23. What kind of pattern are you going to fly, and why?

I think there's a right answer to this question.

best,
Evan

On Monday, August 1, 2016 at 6:59:04 AM UTC-5, Tango Eight wrote:

...pop quiz then.

You're #3 in the pattern behind a student in a 1-34 flying a standard glider pattern and a tow plane. Behind you is another student + CFI in an L-23. What kind of pattern are you going to fly, and why?

Situation number 2: You enter the pattern a bit low (so not enough to orbit) and a student in a L-23 enters the pattern behind and below you - what kind of pattern are you going to fly and why?

There are times when a big "bomber" pattern are necessary and safer; there are also times when you have to get on the ground as fast as possible. A competently trained pilot can adapt to whatever situation is encountered and fly accordingly.

kirk
66

Well, not that my answer matters much as I'm only a six year glider pilot, but I do come from a USAF background.

All else being equal I fly a curved pattern all the way from downwind to final. Flying that pattern does not stop nor preclude cross checks. I do not stare at the land point all the way around. I check the opposite base along my entire downwind leg. I check again throughout my pattern, and I look for straight in traffic prior to passing the 100-110 degree point where it gets under my belly. I also do not stop cross checks into the cockpit to monitor airspeed, altitude and yaw string. That constant cross check and outside look out has been ingrained in me for years. Even on short final I look around, nod to the duty crew, whatever. I have yet to see anything dangerous in this technique. I was taught you fly a pattern to get you to final in the envelop/cone where you still have correction ability on final--i.e. about half speed brakes.

I also fly TLAR... My goal in the pattern, is to hit half brakes all the way around the turn, never changing anything to fly a perfect pattern, roll out, no changes until flare, then touchdown at my aim point. I never quite get there, but that perfection goal challenges and pleases me, and I get pretty close some times. I have been able to fly the same pattern with multiple aircraft in the pattern (almost all of whom fly wider than I do). If I can't time my pattern to follow someone ahead and/or with someone behind, and not conflict with either no matter how I fly, I've got no business flying. Heck, I've held on opposite (right) base to let four gliders land who were in the opposite pattern before I curved my way in behind them in the remaining space.

That said, I am more than capable of flying square patterns, and I actually hit 45 degree or higher bank angles in my turns when I do. I do this when winds are high as a matter of course--the long, lower bank angle, continuous turn allows the winds to affect me more, and I prefer the hard, shorter turns, and the wind corrections and min drag of the straight legs and fast turns to the longer gentler draggier effects of the continuous turn. Less wind drag, less wind effect with the straighter legs it seems to me (i.e. more efficient approach).

My thoughts: my pattern keeps me closer to the field in case of rapid deterioration of flight conditions or glider problems. I find it much easier to visualize the cone and my approach to it as I'm flying it all the way around the pattern. Since I do not have to time the final turn, I have more time to do lookout, cross checks, etc as my flight inputs are relatively minor corrections all the way around. if I need to get down faster, outside rudder works great (practiced it on purpose, but have never required it).

It does make other glider pilots, or instructors at strange field checkouts a little nervous when they fly with me however, as they feel tight and find the constant turn weird or different.... But they have always said I've handled it safely and easily and got on final with zero issues.

Squeak

2G wrote on 7/31/2016 4:07 PM:
I also like to have A LOT of altitude when entering the pattern
(2,000 ft). It is easy to burn off that altitude in modern gliders
and it gives me options if something unexpected happens (like a plane
pulling out onto the runway unannounced). Altitude lost is like
runway behind you - it doesn't do you any good.

I like to have a lot altitude in the pattern, generally entering at 1000
feet agl. I don't like to be any higher, because I worry about
descending onto aircraft below me in the standard pattern (they can be
hard see, and usually are not looking up for aircraft above them). To
avoid that, I descend away from the airport, watching below me, until I
can make a "standard" 45 degree entry to downwind, arriving there in the
1000' - 1200' range. I don't use spoilers until I've turned final, so my
turns to base and to final are relatively high.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "A Guide to Self-Launching Sailplane Operation"

https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

On Monday, August 1, 2016 at 9:27:37 AM UTC-4, kirk.stant wrote:
On Monday, August 1, 2016 at 6:59:04 AM UTC-5, Tango Eight wrote:

...pop quiz then.

You're #3 in the pattern behind a student in a 1-34 flying a standard glider pattern and a tow plane. Behind you is another student + CFI in an L-23. What kind of pattern are you going to fly, and why?

Situation number 2: You enter the pattern a bit low (so not enough to orbit) and a student in a L-23 enters the pattern behind and below you - what kind of pattern are you going to fly and why?

There are times when a big "bomber" pattern are necessary and safer; there are also times when you have to get on the ground as fast as possible. A competently trained pilot can adapt to whatever situation is encountered and fly accordingly.

kirk
66


So: what type of traffic pattern allows the greatest degree of flexibility to meet the needs of a wide variety of situations (traffic, weather, etc.)?


Where I'm going with this: the guy who has made up his mind 5 (or 500) miles out what sort of pattern he is going to fly ("I always...") and sticks to that plan like glue is a pain in the ass (at best).


best,
Evan

On 8/1/2016 9:34 AM, Tango Eight wrote:
Snip...

There are times when a big "bomber" pattern are necessary and safer;
there are also times when you have to get on the ground as fast as
possible. A competently trained pilot can adapt to whatever situation is
encountered and fly accordingly.

kirk 66

Completely agree...

So: what type of traffic pattern allows the greatest degree of flexibility
to meet the needs of a wide variety of situations (traffic, weather,
etc.)?

Is this a trick question?

Where I'm going with this: the guy who has made up his mind 5 (or 500)
miles out what sort of pattern he is going to fly ("I always...") and
sticks to that plan like glue is a pain in the ass (at best).

best, Evan

Completely agree with the PITA bit...nor do I see any fundamental conflict
between the above two views. "Choose wisely," is a great aviation mantra.

FWIW, the only two times I've been "surprised" in the pattern at Boulder (CO,
described earlier in the thread) was from bozo (as in both were experienced
enough and "should have known better [than to do what they did])" glider
pilots, one a visitor, one a local, who entered the pattern (very) late (and
low) from non-standard directions for prevailing conditions, necessitating I
alter my pattern plans, for separation and safety. "Properly educating" locals
is relatively straightforward; the visitor never reappeared & I have no idea
if he learned anything useful from his self-inflicted "idiot's pattern." It
easily could have had something of a bad snowball effect, depending on the
skills and experience of the others in the pattern just then (and there were 2
more in addition to me, as I recall).

Why anyone would thoughtfully choose to fly those sorts of patterns under
busy, benign-weather, conditions is beyond my way of thinking...

Bob W.

On Friday, July 29, 2016 at 5:19:53 PM UTC-5, BobW wrote:

I don't comprehend why a circle-from-downwind-to-final landing pattern in a
glider "...has to be done from a low downwind, and it happens fast." I
understand it CAN be done that way, but not why it MUST be done that way.

Because you are taking out the base leg - and the altitude and time spend exiting the first 90 degree turn, flying the base leg, then entering the second 90 degree turn to final. All this takes time and altitude so either you fly a tight, low downwind and 180 to final, or you fly higher and wider and use 2 90s (or 2 45s and a 90). That's assuming you want to use reasonable angles of bank, not a real shallow 180 turn.

Back to my original puzzlement...am I correct in believing "military approved"
circling approaches essentially do NOT include "a straight final" portion,
a-la the "immediately before touchdown" curving flight path understandably
employed by (e.g.) Pitts biplane pilots as a means of retaining over-the-nose
vision for as long as possible until the runway edges appear on either side of
the nose?

No, it is based on rolling out on final at a comfortable distance from the threshold to allow for the final lineup and xwind correction. In jets it was about 1 mile out, in a glider it can be closer but you still want a comfortable final. The old "continuous turn to touchdown" was used by WW2 fighters (and Pitts', BTDT!) where you couldn't see the runway over the nose on a straight final. But it works nicely in a glider if your front seat passenger has big hair! ;^)

In our sport you take whatever pattern entry you can and should be able to safely land. Yesterday I was working a weak thermal just off the end of our club's runway - I had notified ground ops where I was and could see that there was no conflicting traffic, and used the opportunity to work on low save/landout procedures - which didn't work so I just rolled out at 500' or so and landed straight ahead, rolling up to the clubhouse. No standard pattern, but good training, I think. Some may disagree, and that's fine. I've had to do the same in real landouts and I like practicing non-standard approaches in a safe environment (I was watching the pattern and could break out and land at any time if conflicting traffic appeared). Perhaps that is from military training where you often practice emergency procedures in the air - watch F-16s doing SFO (simulated flame out) approaches sometime - there is an exciting way to land!

Kirk
66

Hi Evan,

Of course you think there's a right answer because you're a proponent of
the square pattern which, if you've read my posts, I'm not at all
against. I just prefer to fly the pattern which works best _for me_ and
to date, nobody has complained about.

That said, I start monitoring the local field from about 20 miles out
and am aware of the traffic situation so I plan ahead and don't get into
the situation of being #3 but should it still happen:

1. I can reduce my speed considerably and pull up to give time to others.
2. Take a thermal and climb
3. Land on the parallel taxiway
4. Land on the cross wind runway
5. Land opposite direction (we have a long runway)
6. Land way long
7. Make a close in pattern in front of the 1-34 who's probably at twice
my distance from the runway. I'll be clear at the taxiway likely before
he turns final.

I'm sure I can think of more ways to mitigate the situation but I don't
feel constrained to drive an aircraft as though it were a train stuck on
the tracks. That's the main problem I see with "by the book" flying.
I'm not an outlaw and don't mean to come across that way, but I have to
sniff when I'm told that there's only one right way to do something.
One of my EE professors back in the early 70s (an old German) used to
sniff at what he called "cooking book engineers". I took that to heart
and try to do what I think is best for a given situation and what works
best for me. I understand that, as a CFI you're pretty much constrained
to teach by the book, but let me ask you this: Is there anything in the
FAA's Glider Flying Handbook that you know to be wrong? Do you teach it
wrong if it's so published or do you teach it right? I do what needs to
be done and yes, I could fly a square pattern in the situation you
described.

And another question: Have you ever seen someone really get into
trouble because the pilot in front of him in the pattern flew way too
far out before turning base and #2 felt that he had to fly even further
to maintain spacing? I have.

Now please tell me your correct answer. I'm genuinely interested and
I've enjoyed this discussion and hope that others less experienced might
undertake to learn to think outside the box.

Regards,
Dan

On 8/1/2016 5:59 AM, Tango Eight wrote:
On Sunday, July 31, 2016 at 10:32:02 PM UTC-4, Dan Marotta wrote:

Fly what works for you and don't disparage techniques that are out
of your sphere of experience.
...pop quiz then.

You're #3 in the pattern behind a student in a 1-34 flying a standard glider pattern and a tow plane. Behind you is another student + CFI in an L-23. What kind of pattern are you going to fly, and why?

I think there's a right answer to this question.

best,
Evan


--
Dan, 5J

Bob,

I doubt anyone tried to fly a bozo pattern. Sometimes we get into a bad
situation and barely scrape home and do the best we can to salvage the
situation. Hopefully the "offending" pilot would apologize to all at
the airport for throwing the proverbial wrench into the works. I do
recall thermalling over a mall parking lot in Boulder once having
mistakenly followed a crow to the back side of the Flat Irons. I
thought it was a hawk and immediately regretted my decision. I don't
recall the pattern I flew that day.

On 8/1/2016 9:55 AM, Bob Whelan wrote:
On 8/1/2016 9:34 AM, Tango Eight wrote:
Snip...

There are times when a big "bomber" pattern are necessary and safer;
there are also times when you have to get on the ground as fast as
possible. A competently trained pilot can adapt to whatever
situation is
encountered and fly accordingly.

kirk 66

Completely agree...

So: what type of traffic pattern allows the greatest degree of
flexibility
to meet the needs of a wide variety of situations (traffic, weather,
etc.)?

Is this a trick question?

Where I'm going with this: the guy who has made up his mind 5 (or 500)
miles out what sort of pattern he is going to fly ("I always...") and
sticks to that plan like glue is a pain in the ass (at best).

best, Evan

Completely agree with the PITA bit...nor do I see any fundamental
conflict between the above two views. "Choose wisely," is a great
aviation mantra.

FWIW, the only two times I've been "surprised" in the pattern at
Boulder (CO, described earlier in the thread) was from bozo (as in
both were experienced enough and "should have known better [than to do
what they did])" glider pilots, one a visitor, one a local, who
entered the pattern (very) late (and low) from non-standard directions
for prevailing conditions, necessitating I alter my pattern plans, for
separation and safety. "Properly educating" locals is relatively
straightforward; the visitor never reappeared & I have no idea if he
learned anything useful from his self-inflicted "idiot's pattern." It
easily could have had something of a bad snowball effect, depending on
the skills and experience of the others in the pattern just then (and
there were 2 more in addition to me, as I recall).

Why anyone would thoughtfully choose to fly those sorts of patterns
under busy, benign-weather, conditions is beyond my way of thinking...

Bob W.

--
Dan, 5J

On Sunday, July 31, 2016 at 7:32:02 PM UTC-7, Dan Marotta wrote:
In all other situations a square pattern (or a modified square pattern) is far safer. Flying a button hook pattern puts the runway out of sight to the pilot, so it is hard to judge how far you have flown, making it much more likely that an overshoot or undershoot landing will occur.

What???Â* I always fly a descending 180 to short final and I never
lose sight of the runway.Â* What are you doing that puts you in that
position?Â* It's trivial to keep the landing point in view over your
shoulder until you begin the turn, unless you're flying way too far
out before beginning your final.


An important aspect of the square pattern, in addition to the visibility part, is to assess the winds aloft by the amount of crab required.

It's easy to assess winds on downwind and continuously through the
final turn without losing sight of the touchdown point. Drift is
recognized with peripheral vision and quick glances down at the
ground.Â* Final and opposite patterns are monitored from downwind
throughout the final turn.Â* Angle of descent is easily controlled by
keeping the angle to the touchdown point constant.




I have been flying lately in conditions of high cross winds (10-20 kt) and even higher gusts (20-30 kt). Having a stabilized base leg is essential to judge this

As said above, it's easy to judge during the downwind and throughout
the turn.


(the AWOS is just to old to be relied upon).

Very true!


If I were to fly a button hook pattern I would have a ground speed of 110-130 kt, given the high density altitudes we are flying and an 80 kt IAS (100 kt TAS + 10-30 kt tail wind)!

Why would you have a higher ground speed in turning flight than in
straight flight?


This translates to up to 220 ft/sec (a 180 deg turn takes 10-20 sec and complicates the design point on when to start the turn). If you hit unexpected sinking air during this turn you could be in a real pickle!

No, you're close enough that reducing dive brake will compensate for
any sink.Â* If you're in a location with known high sink on final,
e.g., Salida, CO, you should make your turn at the proper height and
distance from the runway.


You may not experience these conditions where you fly, but a lot of accidents occur when flatlanders venture into high density altitude airports.

I also like to have A LOT of altitude when entering the pattern (2,000 ft).

There goes flying where other pilots expect to see you!


It is easy to burn off that altitude in modern gliders and it gives me options if something unexpected happens (like a plane pulling out onto the runway unannounced). Altitude lost is like runway behind you - it doesn't do you any good.

Tom


Fly what works for you and don't disparage techniques that are out
of your sphere of experience.


--

Dan, 5J



On Sunday, July 31, 2016 at 7:32:02 PM UTC-7, Dan Marotta wrote:
In all other situations a square pattern (or a modified square pattern) is far safer. Flying a button hook pattern puts the runway out of sight to the pilot, so it is hard to judge how far you have flown, making it much more likely that an overshoot or undershoot landing will occur.

What???Â* I always fly a descending 180 to short final and I never
lose sight of the runway.Â* What are you doing that puts you in that
position?Â* It's trivial to keep the landing point in view over your
shoulder until you begin the turn, unless you're flying way too far
out before beginning your final.


An important aspect of the square pattern, in addition to the visibility part, is to assess the winds aloft by the amount of crab required.

It's easy to assess winds on downwind and continuously through the
final turn without losing sight of the touchdown point. Drift is
recognized with peripheral vision and quick glances down at the
ground.Â* Final and opposite patterns are monitored from downwind
throughout the final turn.Â* Angle of descent is easily controlled by
keeping the angle to the touchdown point constant.




I have been flying lately in conditions of high cross winds (10-20 kt) and even higher gusts (20-30 kt). Having a stabilized base leg is essential to judge this

As said above, it's easy to judge during the downwind and throughout
the turn.


(the AWOS is just to old to be relied upon).

Very true!


If I were to fly a button hook pattern I would have a ground speed of 110-130 kt, given the high density altitudes we are flying and an 80 kt IAS (100 kt TAS + 10-30 kt tail wind)!

Why would you have a higher ground speed in turning flight than in
straight flight?


This translates to up to 220 ft/sec (a 180 deg turn takes 10-20 sec and complicates the design point on when to start the turn). If you hit unexpected sinking air during this turn you could be in a real pickle!

No, you're close enough that reducing dive brake will compensate for
any sink.Â* If you're in a location with known high sink on final,
e.g., Salida, CO, you should make your turn at the proper height and
distance from the runway.


You may not experience these conditions where you fly, but a lot of accidents occur when flatlanders venture into high density altitude airports.

I also like to have A LOT of altitude when entering the pattern (2,000 ft).

There goes flying where other pilots expect to see you!


It is easy to burn off that altitude in modern gliders and it gives me options if something unexpected happens (like a plane pulling out onto the runway unannounced). Altitude lost is like runway behind you - it doesn't do you any good.

Tom


Fly what works for you and don't disparage techniques that are out
of your sphere of experience.


--

Dan, 5J

First off, I DIDN'T disparage anybody, but you certainly are. You have NO IDEA what my "sphere of experience" is, or my experience in general.

My original contention stands: a square pattern is far safer than a button hook pattern.

I DIDN'T say that your ground speed increases during your downwind turn. The point was you are covering a lot of ground fast and can end up further away from the runway than you expect.

You agreed that you CAN lose sight of the runway; not losing sight requires a tight "carrier landing" turn which precludes a stabilized final. This is okay if the situation dictates, low altitude or an expedited landing for traffic, but is generally less safe than a square pattern.

You are trying to convince others of the superiority of your technique and I am offering the opposite side of the discussion. You need to calm down and discuss things rationally.

Tom