Any Advice for Precision Flying in Rough Air?

MBDiagMan

MBDiagMan

Final Approach
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I can fly my little Cessna 140 on instruments in smooth air and create a track log that looks as if it were drawn with a straight edge. I have a 420 on the panel and I can match the TRK to the DTRK and draw a straight line. Bumpy air is a different story. It is still a ragwing and moves dramatically with every little bump.

I realize that most of the advice here will be to fly under the hood in a more stable platform, but that’s not what I am trying to do. I am trying to improve my instrument flying precision in this plane.

I normally try to hold it on course with the rudder while keeping the wings level. Works great in smooth air. Is there something I need to add to the mix in bumpy air that will help my precision in those conditions?

BTW, the one answer I have for my own question is “more practice” and I am working on that.
 
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Relax and just roll with the bumps. White-knuckling the yoke and fighting every bump will only result in a very exhausting, stressful flight.

You just gotta loosen up, maybe slow the plane down a bit(If it’s very bumpy you should be at/below Va anyway), and trust the plane to just do its thing while you guide it in the right direction. You’re gonna see some minor deviations as the tail moves around but just keep it trending on-course with small, relaxed corrections
 
You have to be willing to give up on the precision in turbulence, especially in such a lightly loaded airplane. Keep the wings level and the g loads reasonable. Much easier on the airplane and the person flying it.
 
Focus on flying a specific heading, as you drift off course, change to another (appropriate) heading to fly. Even in heavier aircraft, this leads to a smoother flight path than when 'chasing needles.' I think the update rate of a GPS displaying TRK is not fast enough to avoid zig-zag flight path, compared to a DG. You can easily demonstrate the result, fly your 'normal' course-following routine, then after a while, forget the course and simply fly a specific heading, as if given a vector from ATC. Compare flight paths and see which is smoother. Of course, the idea, as you know, is to figure out what heading is required to maintain your desired course line. And, certainly, turbulence will make your path relatively less steady than smooth air, no matter what plane you might be flying.
 
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Yes, don't try to fly with precision. Do the best you can, and keep it within limits, but don't chase every excursion.
 
MBDiagMan said:
I can fly my little Cessna 140 on instruments in smooth air and create a track log that looks as if it were drawn with a straight edge. I have a 420 on the panel and I can match the TRK to the DTRK and draw a straight line. Bumpy air is a different story. It is still a ragwing and moves dramatically with every little bump.

I realize that most of the advice here will be to fly under the hood in a more stable platform, but that’s not what I am trying to do. I am trying to improve my instrument flying precision in this plane.

I normally try to hold it on course with the rudder while keeping the wings level. Works great in smooth air. Is there something I need to add to the mix in bumpy air that will help my precision in those conditions?

BTW, the one answer I have for my own question is “more practice” and I am working on that.
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Using rudder to hold heading is poor technique. Yaw is not the cause of the problem. Use a very shallow bank and speed up your scan.
 
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MBDiagMan said:
I can fly my little Cessna 140 on instruments in smooth air and create a track log that looks as if it were drawn with a straight edge. I have a 420 on the panel and I can match the TRK to the DTRK and draw a straight line. Bumpy air is a different story. It is still a ragwing and moves dramatically with every little bump.

I realize that most of the advice here will be to fly under the hood in a more stable platform, but that’s not what I am trying to do. I am trying to improve my instrument flying precision in this plane.

I normally try to hold it on course with the rudder while keeping the wings level. Works great in smooth air. Is there something I need to add to the mix in bumpy air that will help my precision in those conditions?

BTW, the one answer I have for my own question is “more practice” and I am working on that.
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I'm not sure how much precision to expect in a C-140 in "bumpy weather." Or even how much is desireable. My L8 is like being in a small ship on a bumpy ocean. Perfection is impossible. However, it's just like the visitor who asked a New Yorker how to get to Carnegie Hall . . . Practice.
 
In a lightly loaded light sport plane you learn to live with not drawing a straight line through the sky. It can be fatiguing chasing every bump that comes along. Keep in mind that corrections are turns and when the stick moves the rudder should also. But in truth most pilots (myself included) don't always do that for minor deviations.

I recently purchased a single axis auto pilot (wing leveler) that should reduce some of the workload but in rough air I still slow down, hand fly the airplane, and roll with the flow.
 
MBDiagMan said:
I normally try to hold it on course with the rudder while keeping the wings level. Works great in smooth air. Is there something I need to add to the mix in bumpy air that will help my precision in those conditions?
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Always use the ailerons to correct course (even the tiniest changes), and the rudder only to eliminate any adverse yaw. You're discovering that while you can get away with small skidding turns (aka "boat turns") in smooth air, they really come to bite you in turbulence.

While using the rudder for (say) a 2-deg course correction isn't dangerous in itself (just inefficient), but getting in the habit of thinking of the rudder as a course-changing control is. Correcting rudder misuse was one of Wolfgang Langwiesche's main focuses in Stick and Rudder in 1944, and sadly, almost 80 years later, rudder-induced accidents (such as using the rudder to "tighten" the turn from base to final, and the resulting stall-spin) are still common.
 
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Thanks very much everyone! I will try putting these suggestions in the mix.

I think that I will begin by trying to fly the heading bug in the choppy air instead of chasing the TRK. That works fine in smooth air, but I think it probably is too slow to refresh for choppy air. That method works fine in smooth air.

I’m out of pocket this week, but I’ll try to fly in the next week or two and will report back with results.
 
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MBDiagMan said:
Thanks very much everyone! I will try putting these suggestions in the mix.

I think that I will begin by trying to fly the heading bug in the choppy air instead of chasing the TRK. That works fine in smooth air, but I think it probably is too slow to refresh for choppy air. That method works fine in smooth air.

Im about of pocket this week, but I’ll try to fly in the next week or two and will report back with results.
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Yours could be an exception, but I think most C-140s are equipped only for VFR flight. If you're VFR, looking out the window might be easier than chasing the little heading bug, and it will keep your eyes outside where the traffic is. Just cross-check with the compass every couple of minutes (quick glance).
 
I find a well trimmed plane with exceptionally light yoke grip can make it even easier. The plane rolls to the right- light yoke pressure you instinctively bank a bit left. Think of your self snd floating inside the plane.
 
One more piece of advice. Every control change you make requires movement in all three axes — if you yaw, or roll, you'll get a pitch change; if you pitch up or down, you'll get a yaw change; etc. The effect is small with small movements, but becomes very noticeable with larger ones, like you're making in rough air. If you correct for just one thing — e.g. the nose suddenly drops, and you pull it up, or the plane rolls and you correct it — you'll have a follow-up movement in at least one other axis, and you'll mistake that for turbulence (rather than PIO — pilot-induced oscillation) and correct it, which triggers an other reaction, and so on, until most of the turbulence is coming from inside the plane instead of outside it.

If you pull up the nose or left wing after it drops, apply a little right rudder as well; if you push the nose down or pull up the left wing after it drops, apply a little left rudder at the same time. If the nose yaws to the left and you want to pull it back straight, use ailerons and rudder (not just rudder alone), and also watch the pitch.

It doesn't take much, but you'll quickly find that once you get a feel for it, you can damp out most of the turbulence with coordinated control inputs.
 
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David Megginson said:
Yours could be an exception, but I think most C-140s are equipped only for VFR flight. If you're VFR, looking out the window might be easier than chasing the little heading bug, and it will keep your eyes outside where the traffic is. Just cross-check with the compass every couple of minutes (quick glance).
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Most are. This one legally files slash golf. ATC watches for traffic.
 
Kevin Holbrook said:
You have to be willing to give up on the precision in turbulence, especially in such a lightly loaded airplane. Keep the wings level and the g loads reasonable. Much easier on the airplane and the person flying it.
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This^^
 
More nuggets. Thanks for the good coaching guys! This is definitely one of the most helpful threads I ever started. You guys were polite and very helpful. Thanks a bunch!
 
Something I do is keep an eye on the VSI (hey, that rhymes!j. If it starts moving up, I start applying a little down pressure and vice versa. The thermals in the summer can shoot the airplane up at 500 fpm (or more) then a few minutes later you are descending at 200 or 300 fpm. The updrafts seem to me to be worse.
 
I have been thinking about this a lot and processing the discussion.

It occurred to me that flying the Mooney with the wing leveler and ailerons linked to the rudder, is a different situation. In that case keeping on track with the rudder pedals might be the way to go. Taking it further, doing the same kind of flying in the Mooney might have put some habits in the mix that don’t transfer well to the no wing leveled, no linked rudder of the 140.
 
Yea our ol rag wings are quite the ride in rough air... cross crossing the country and doing some mountain flying in my 47 c140 it’s just a rough ride at times...

being less than home sick angels I’ve too often failed at not climbing for smoother air. Thinking I’m already slow I don’t want to take even longer to climb up... but I’ve been getting over that as my GF loves to fly and will go anywhere anytime but she does not like the bumps when they get severe... coming home from FL we got the crap kicked out of us over GA and I rode it out till even I was exhausted, stopped took a rest, next leg I took the time to get to 6500 instead of 3.... feels oddly high in that bird but man was it worth it! Such a simple thing we all know in theory snd yet repeatedly I have not taken the time to climb for smoother air...
 
Huckster79 said:
Yea our ol rag wings are quite the ride in rough air... cross crossing the country and doing some mountain flying in my 47 c140 it’s just a rough ride at times...

being less than home sick angels I’ve too often failed at not climbing for smoother air. Thinking I’m already slow I don’t want to take even longer to climb up... but I’ve been getting over that as my GF loves to fly and will go anywhere anytime but she does not like the bumps when they get severe... coming home from FL we got the crap kicked out of us over GA and I rode it out till even I was exhausted, stopped took a rest, next leg I took the time to get to 6500 instead of 3.... feels oddly high in that bird but man was it worth it! Such a simple thing we all know in theory snd yet repeatedly I have not taken the time to climb for smoother air...
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I think that's a good idea. I used to fly my whole family (spouse, two kids, and dog) for long trips in my Piper PA-28-161, and it was always the right choice to climb for smoother air, no matter what the headwind situation was.

With just me alone most of the time now, I sometimes prefer flying a bit lower, and navigating by chart and pilotage (following the magenta line kills most of the fun of flying).
 
David Megginson said:
I think that's a good idea. I used to fly my whole family (spouse, two kids, and dog) for long trips in my Piper PA-28-161, and it was always the right choice to climb for smoother air, no matter what the headwind situation was.

With just me alone most of the time now, I sometimes prefer flying a bit lower, and navigating by chart and pilotage (following the magenta line kills most of the fun of flying).
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yessir! On all. Yea by myself the only time I’d climb over 2-3k would be if terrain called for it :)
 
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MBDiagMan said:
Yeah, too bad I can’t shoot approaches above cloud layer where the air is smooth.
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If you're handflying those approaches in afternoon turbulence, that's where a disciplined scan really starts to pay off. If your attention drifts for only a few seconds, it can be hard to reestablish and restabilise, and the resulting PIOs will amplify the turbulence.
 
I do keep tight rudder and I focus on the scan.

What I plan trying next time is tweaking the bug on the DG so as to keep DTRK and TRK matched and spend most of the time flying the bug. This should tighten my scan.

I might get my chance to try it this afternoon.
 
I flew around the patch in choppy air today. I took up the heading to the IAF, got the DTRK and set it into DG Bug. Flew the bug with an occasional check of the TRK. Turned onto the feeder route, set the bug, then onto the path to the FAF same thing. Just kept flying the bug and got off track once by one mark on the CDI, but reeled it back in. Except for getting about fifty feet low before turning off of the feeder route, it was an acceptable approach.

Thanks so much guys! I think a little more practice and I will be able to do a choppy air ILS well enough to get my instructor ready to sign me off.

You guys rock!
 
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