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I've been doing some searching for a decent way to pass on the concept and importance of "stabilized approaches" for both VFR and IFR flying.

I just found a very good video on the subject through the FAA Wings program -
Course ALC-413 Accident Causal Factors Series - Stabilized Approaches.

In case anyone is interested in the subject, here's a link to the video:
https://www.faasafety.gov/gslac/ALC/Cou ... px?cId=413
(I think this webinar was done in 2015)

Since one of our recent topics was "Let's get out there and wreck some planes", perhaps reviewing "Stabilized Approaches" will help us "...not wreck our Diamonds! "

The video runs for about 45 minutes (and you can even get "FAA Wings" credit !!)

If you decide to watch it, please post your feedback. Thanks!

In the airline world where I come from a "stabilized approach" is THE big topic in training and on the line. We have a stabilized approach criteria that if not met while going through gates at 1000' and 500' a MANDATORY missed approach must be executed. We have a system on board called FOQA that rats everyone out and your data is sent to be analyzed. Reports are given on the occurrences of unstabilized approaches and go arounds.

Adopt a stabilized approach criteria that works for your operation and stick to it. Hold yourself accountable.

The problem I have with the concept of stabilized approaches as applied to small piston engine planes is that it goes contrary to the training you get when going for the single-engine Commercial pilot's license. One of the most valuable Commercial maneuvers is the "power-off 180 degree spot landing," where you pull the power to idle when abeam the numbers flying the traffic pattern -- and try to land - 0, +200 feet of a spot on the runway.

It's anything BUT a stabilized approach as you make a relatively steep turn back to the runway -- adjusting your curved path, deciding when to apply flaps, and perhaps performing a forward slip to lose altitude -- in order hit your target on the runway. This is great practice should you ever lose your engine and need to put the plane down in a small field. There are some pilots of single-engine planes who fly this way routinely, with the assumption that they're still going to make the runway if their engine quits while flying in the traffic pattern. Also it's not unusual for tower controllers to request pilots of piston aircraft to fly short non-stabilized approaches in order to sequence multiple aircraft onto a busy runway. (This happens a lot at EAA AirVenture Oshkosh.)

Obviously this is very different from flying a multi-engine jet airliner on a straight-in ILS approach. But IMHO piston aircraft pilots should also be proficient at flying non-stabilized approaches.

"But IMHO piston aircraft pilots should also be proficient at flying non-stabilized approaches."

Very true Dave - I agree that you should be competent at both! My main reason for posting the video link was to get guys to think about "being in control" of their airplane versus "riding along" and accepting what they are "getting" from the plane.

As far as I'm concerned, flying a "stabilized approach" is making the plane do what YOU/I want it to do. If that's not happening, then we need to make a good and timely correction to get it there.

I think that FAA video does a good job of explaining "why" stabilized approaches are important overall, especially when doing an instrument approach, whether you're in a 5000# plane or a 500,000# plane.

jb642DA wrote: ↑Tue May 14, 2019 2:52 am "But IMHO piston aircraft pilots should also be proficient at flying non-stabilized approaches."

Very true Dave - I agree that you should be competent at both! My main reason for posting the video link was to get guys to think about "being in control" of their airplane versus "riding along" and accepting what they are "getting" from the plane.

As far as I'm concerned, flying a "stabilized approach" is making the plane do what YOU/I want it to do. If that's not happening, then we need to make a good and timely correction to get it there.

I think that FAA video does a good job of explaining "why" stabilized approaches are important overall, especially when doing an instrument approach, whether you're in a 5000# plane or a 500,000# plane.

Righto - As long as you know whether you've got it or it's time to fold 'em and go around. I've had occasions to discover late on final approach that suddenly I don't have all the runway I thought I was going to have due to someone deciding a stop-and-go included a coffee break and discussion of the relative philosophies of Sartre vs. Nietzsche. Go around or go deeper into the back side and land short? I've made both choices at different times and both have been right. The DA40 is a good partner for these kinds of exercises. You do have to know your airplane's capabilities.

I would also point out that the spool-up time on a turbine probably makes a stabilized approach a little more important. A last minute change in my DA40's power was always instantaneous and you could wiggle things all the way to the pavement.

In the worst conditions that I have landed, with gusty winds, cross winds, and wind shear from terrain and obstacles, the approach to ground effect was definitely unstable, but the landing (since I was INCREDIBLY focused on landing) was often really smooth. On (Morristown, NJ) prompted the tower to say, "N971RD, nice landing. That was the smoothest we've seen today and these are tough conditions." Since I had the family in the plane, I liked hearing that. A bizjet captain piped up with, "What about mine? I thought it was pretty good," prompting the tower to reply, "You left a big oil spot on the runway."

I would be interested in what people think of my experiences in this area.

My last single engine instructor that I had insisted on a stabilized approach for IFR and wanted no configuration changes after the FAF. Set the flaps, gear and throttle and then only minor throttle changes from there on out.

However, when I went to a different flight school to work on my ME rating in a DA42, the instructors at that school all followed the same protocol: gear, throttle, and one notch of flaps at the FAF, but go to full flaps once committed to the landing. E.g. on an ILS to 200' minimums, apply full flaps upon breaking out.

Then when I went on to transition training to the DA62 at a different flight school, the instructor there and a Diamond factory pilot I flew with both had essentially the same technique as my single engine instructor had for an instrument approach, i.e., only one notch of flaps throughout the approach and landing.

Over the past year I've flown my DA62 both ways numerous times but have settled on going to full flaps once committed to the landing. My reasoning? A) I need to slow from my approach speed of 105 KIAS to Vref anyway so that requires a significant throttle change if there are no flaps changes. Applying full flaps pretty much takes me from 105 KIAS to Vref w/o much of a throttle change so it seems to be six of one, half dozen of the other. and B) engaging full flaps also does a gear check as well and I feel that having a second check besides the throttle position isn't hurting anything.

--Ron

Colin wrote: ↑Tue May 14, 2019 2:15 pm I would also point out that the spool-up time on a turbine probably makes a stabilized approach a little more important. A last minute change in my DA40's power was always instantaneous and you could wiggle things all the way to the pavement.

In the worst conditions that I have landed, with gusty winds, cross winds, and wind shear from terrain and obstacles, the approach to ground effect was definitely unstable, but the landing (since I was INCREDIBLY focused on landing) was often really smooth. On (Morristown, NJ) prompted the tower to say, "N971RD, nice landing. That was the smoothest we've seen today and these are tough conditions." Since I had the family in the plane, I liked hearing that. A bizjet captain piped up with, "What about mine? I thought it was pretty good," prompting the tower to reply, "You left a big oil spot on the runway."

In addition to the, "Thanks" icon, it would be nice to have a "Like" button too. If so, I would have clicked it on your post above.

Don wrote: ↑Tue May 14, 2019 4:00 pm In addition to the, "Thanks" icon, it would be nice to have a "Like" button too. If so, I would have clicked it on your post above.

Yes! Another forum on which I'm active has a variety of choices including Funny, Informative, Helpful, Like, Disagree and Love. Here it's just a thumbs up and the person who posts will have to guess why.

Not complaining, just commenting.

The value of discussions like this isn't to be able to recite the catechism of numbers, but to make you think about being ahead of the plane and the circumstances of the next few minutes of your life. Popping out at 250 ft on a straight-in 200-ft minimum approach to a 6,000-ft. runway isn't the same thing as a 600-ft circling breakout to a 3,000-ft. runway 90 degrees off your heading with the threshold 1/2 mile away.

Musing on approach speeds, the POH for the DA40 lists speeds that are conservatively high. The old 1.3 x Vso rule of thumb is something to know and keep in your back pocket.

Example: At my not uncommon weight of 2130 lb or so, 1.3 x Vso would be roughly 53 KIAS. Approach speed per the POH is 61-62 KIAS. On my normal 5700-ft runway with the first reasonable turnoff a couple thousand feet down the runway, 60-ish is fine. Lots of float, but no big deal. On the other hand, landing on the now-defunct (Vancouver, WA) Evergreen Airport's 2,000-ft. runway dictated more discipline: 50-55 KIAS. Using 60 KIAS resulted in one of my more memorable go-arounds (Full-flap go-around from a 2-ft. height following a seemingly interminable float down the runway. Did I mention the fence with the towering shrubbery about 10 ft. off the end?). At the slower speed on the second try it was a total non-event.

It's not unusual to have a stabilized approach become unstable in the last 200 ft. of descent. I've seen a nice constant airspeed (no obvious gusting) zoom downward coming over the threshold as trees or the macro-boundary layer gets involved. A neat trick: if there's wind compare groundspeed, IAS, and reported winds to anticipate a possible shear.