Piper clips semi trailer on short final...

I looked at AZPilot's screen capture, and assuming that the scale is accurate, a stabilized approach to the threshold on a 3 degree slope would have the clearance above ground-level as it passed over the edge of a 13'6" truck parked right at the edge of the shoulder would still be 4'4" (17'10" AGL).

The problem with that calculation is that it assumes that the road surface is at the same elevation as the runway threshold. With 340' between the threshold and the edge of the shoulder, I would not be comfortable making that assumption.

I will not voice an opinion on the prudence of a 3 degree stabilized approach to the threshold for an experienced pilot, but at my sub 100-hour experience, I would make it steeper and aim a bit further down the runway.

For the sake of full disclosure, I will share that my instructor wouldn't allow me to make stabilized approaches at all. It was "cut the power abeam the numbers" every time (except when he would do something unexpected to screw with me). My DPE was aware of this from some conversations that we had during the oral, and he pumped up my confidence by telling me that it would not be a challenge at all since we had just discussed the procedure and I knew all of the details. He let me do a landing to the PTS using the method that I was taught, and then casually said "let's try one with a stabilized approach." He said he wouldn't fault me if I wanted to extend my downwind beyond what we had discussed in the oral in order to give myself more time to work out the details. I asked about the opposite, staying closer to what I know and doing it a bit steeper than we had discussed in the oral. He said that was fine too. I ended up going out about twice as far as I usually would with the power off, and then finding the urge to turn overwhelming, was pretty high for an approach to my assigned touchdown point. I put in flaps and found the power setting that would let me hit the mark. It was steeper than most would choose for a stabilized approach, but still much shallower than I was used to. I told him that I could make it, but I was not sure that it would prove to him that I could do a stabilized approach. He replied, "I already know that you can do it. I just need to be sure that you know. If you make a safe landing within the PTS range for the touchdown, I suspect that would prove it to yourself." I landed a bit long, but still safely within the PTS.
 
I'd be curious to know what the slope is if you're on the PAPI correctly. Stands to reason that 26 has one because of the proximity to the interstate as well as the frontage road that is closer yet to the threshold.
 
Two things that do you no good. The air above you and the pavement behind you.

I try to hit the numbers to keep my STOL skills sharp.

Pick a point and hit it. Don't three degree it in somewhere around 1000' down the runway. That's sloppy. :nono:
 
MAKG1 said:
On a 2400 foot runway, that uses up a whole lot of margin.

I land PA28s on 2400 foot runways all the time; it's not that hard, unless you're fast. But if I'm going to set down 1000 feet past the threshold, I'll go around. Using normal techniques, not short field (unless I'm in a big hurry and want to make the second turn off in no wind).

Not necessarily on the numbers, but certainly in the first third.
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I probably should have put the caveat "unless more runway is needed for a safe landing" in my post.

That said, 2400 is still reasonable to NOT need to land on the numbers.

My point is, with a road so close, we know there must me a displaced threshold and he was dragging it in. If not, there is an error in the airport layout.
 
azpilot said:
15 or 16 feet was a total guess on my part. I looked at the airport in google maps. The southbound lane of the interstate closest to the airport is 350' from the reduced threshold. If you look at a 3 degree glide path that would put you 18.3 feet above the ground when 350 feet from the runway.

I am pretty sure I did something wrong. The trig is right. But I made a mistake somewhere else. Likely in one of my assumptions...
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One assumption is that the threshold elevation and the interstate elevation are the same. May or may not be true.
 
Stevel said:
I looked at AZPilot's screen capture, and assuming that the scale is accurate, a stabilized approach to the threshold on a 3 degree slope would have the clearance above ground-level as it passed over the edge of a 13'6" truck parked right at the edge of the shoulder would still be 4'4" (17'10" AGL).

The problem with that calculation is that it assumes that the road surface is at the same elevation as the runway threshold. With 340' between the threshold and the edge of the shoulder, I would not be comfortable making that assumption.

I will not voice an opinion on the prudence of a 3 degree stabilized approach to the threshold for an experienced pilot, but at my sub 100-hour experience, I would make it steeper and aim a bit further down the runway.
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OK, so I 're-measured' the distance using google maps again. If I measure from what appears to the spot the PAPI are located, to the nearest lane of the freeway, I get 390'. Plus as someone pointed out, this won't put you down on the numbers, you'll be slightly above the numbers. On top of that, we don't know the elevation difference between the runway and the freeway. Nor do we know the angle the PAPI are set for.

If I use 390 feet and a 3.5 degree glide path, that puts the plane 24 feet above the highway. This still doesn't account for any elevation distance.

Bottom line... He was low... I guess I didn't need all that math and trig to tell me that...
 
The Milwaukee, Wisconsin, Federal Aviation Administration Flight Standards District Office Principal Operations Inspector said his office has had complaints of low flying airplanes by drivers on the interstate highway that is about 300-feet from the runway's threshold. The displaced threshold begins about 160-feet from the interstate highway. During subsequent investigation activity, the IIC observed airplanes flying about 20 to 50-feet above the vehicles that were using the highway as the airplanes approached to land. Some airplanes landed on the displaced threshold. The displaced threshold markings on runway 26L were weathered and very light in color.
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This is from the '97 report...
 
Kritchlow said:
I probably should have put the caveat "unless more runway is needed for a safe landing" in my post.

That said, 2400 is still reasonable to NOT need to land on the numbers...
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Agreed. I learned to fly at the same 2400 foot runway (actually 2443) that MAKG is talking about, and I was taught to use the numbers as an aim point. Then the flare, combined with ground effect, puts my touchdown point a suitable distance down the runway.
 
Palmpilot said:
Agreed. I learned to fly at the same 2400 foot runway (actually 2443) that MAKG is talking about, and I was taught to use the numbers as an aim point. Then the flare, combined with ground effect, puts my touchdown point a suitable distance down the runway.
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I did my primary training, and later taught, at an 1800' strip. We thought nothing of landing 1/2 way down the strip... Even when snow covered.

In retrospect that may have been foolish, but point is it can easily be done if needed.
 
fiveoboy01 said:
Remember that a 3 degree glide path assumes you're touching down 1000' down the runway. For purposes of an instrument approach anyways.

I'd venture to say that a small piston single can easily make an approach to a short runway significantly steeper than 3 degrees with no issue.
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The PAPI at Palo Alto Airport (PAO) is four degrees, for example.
 
Kritchlow said:
I did my primary training, and later taught, at an 1800' strip. We thought nothing of landing 1/2 way down the strip... Even when snow covered.

In retrospect that may have been foolish, but point is it can easily be done if needed.
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A lot depends on the ground roll of what you're flying, IMO.

I may have touched down half-way down Palo Alto's runway on occasion, but I try not to make a habit of it. But I agree that trying to touch down ON the numbers is not a safe practice. Even for people whose spot landing skills are top notch, there's always the possibility of an unexpected downdraft at just the wrong time.
 
Palmpilot said:
A lot depends on the ground roll of what you're flying, IMO.

I may have touched down half-way down Palo Alto's runway on occasion, but I try not to make a habit of it. But I agree that trying to touch down ON the numbers is not a safe practice. Even for people whose spot landing skills are top notch, there's always the possibility of an unexpected downdraft at just the wrong time.
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Yup... That is the UNexpected buffer zone. If you intentionally eat that up there is no margin for the unexpected (or less than perfect human) happenings.
 
bigred said:
This is from the '97 report...
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The runway (and entire airport) has been completely refurbished since '97, with new asphalt and markings.

We were based on that field (Sylvania Field, C89) until '97, when we moved to Iowa. We rented that accident Cherokee 140 every Saturday for years, and have often speculated how strange it is that this girl would likely still be alive if I hadn't started a business in Iowa... But I digress.

Sylvania had a 2300' runway, just 30' wide, when we were based there. I landed there in all weather, including at night, with snow piled on either side of the runway. When Mary learned to fly on the (then) three big, wide runways in Iowa City, IA, I sent her back to Sylvania to learn how to land. Nothing teaches precision like a short, narrow strip.
 
Palmpilot said:
The PAPI angle is in the A/FD for some airports, but not for the one in question.

https://skyvector.com/airport/C89/Sylvania-Airport
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Yeah I noticed no angle was given.

My GUESS, based on the trig info given by some of the mathematically-gifted guys in the room, is that if you're white/red, you're higher than you would be with a true 3 degree slope. It makes sense that it's on that runway due to the proximity of the interstate.
 
Jay Honeck said:
Nothing teaches precision like a short, narrow strip.
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Damn straight! My dad's airplane is hangared here and when I rented it, I was in and out all the time. I've landed my Archer here quite a few times too.

2200x26(AFD says 30, but I got a tape measure out).. with a dip in the middle. It makes landing anywhere else child's play:D

unnamed-L.jpg
 
Speaking of precision, that plane appears to be lined up on the left half of the runway!
 
I don't remember if it was or not.. maybe slightly so. A friend in the right seat took the photo, so I'm not sure if the camera angle had anything to do with it.... but if I was off centerline, I corrected before touchdown. This was literally a couple days after taking delivery and I didn't have a lot of time in the Archer yet. If you're much off the centerline, you're likely to have a main in the grass:)

A LOT of guys just land in the grass on the left. It's twice as wide and at some point the runway lights were moved to the left so one could land on either surface.

In the winter, a few guys use skis on the grassy part.
 
Stabilized approaches are fine, but that 3 degree **** for a VFR approach is stupid especially in this case. Learn how to do a frucking steep approach to clear obstacles to get into a short field.

I cringe every time I fly with someone who drags it in on the prop because they have to be on glideslope. I realize engines don't crap out that often anymore, but if your motor craps the bed you're hosed.
 
I thought us Pilots do have sort of magic power :yes:

fiveoboy01 said:
The guy in the video makes it sound like landing on a short strip requires some sort of magic... baloney... I have landed many times at my dad's airport which has a 2300 foot runway and a displaced threshold and a road much closer... and I can clear the top of any traffic quite easily. A semi trailer no, but you can see the road in this picture:

unnamed%20%2832%29-L.jpg


The interstate at that airport is a LOT farther from the threshold.

This guy plain screwed up with how low he was.
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Seriously I'd just slip it in to clear the traffic on the Interstate. I've flown in there before, and if you are paying attention it shouldn't be an issue.

I do remember the girl that died there back in the late 90's and that was a bad deal, but preventable.
 
At times my approaches seem to rival the space shuttle for steepness.
 
fiveoboy01 said:
I don't remember if it was or not.. maybe slightly so. A friend in the right seat took the photo, so I'm not sure if the camera angle had anything to do with it.... but if I was off centerline, I corrected before touchdown. This was literally a couple days after taking delivery and I didn't have a lot of time in the Archer yet. If you're much off the centerline, you're likely to have a main in the grass:)
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If it were caused by the photographer being in the right seat, it would make it look like the plane was to the right of the centerline, not to the left.
 
Well then I wasn't lined up. Shrug.

Out of curiosity I looked at several videos and I do have a tendency to be left of centerline most of the time. I'll work on it:)
 
fiveoboy01 said:
Well then I wasn't lined up. Shrug.

Out of curiosity I looked at several videos and I do have a tendency to be left of centerline most of the time. I'll work on it:)
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Very common tendency.

1) Auto drivers are conditioned to their eyes being in the left of their lane. I think that can subconsciously transfer over.

2) Many pilots are trained to shift their view to the left runway edge in the flare, as the nose may block their view down the runway. This may result in a last minute pull to the left since our bodies tend to follow our eyes.

Best solution is to consciously try to put the centerline between your feet and keep it there. The plane may then touch down ever-so-slightly right of the centerline in a side-by-side configuration, but not enough to matter. In a tandem, of course, you're golden!
 
timwinters said:
Huh?

:dunno:
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I understood him to be implying that the photographer's being in the right seat might be why the plane in his photo appears to be lined up on the left side of the runway.

I was trying to describe why that explanation wouldn't work: If the plane were actually perfectly lined up on the center of the runway, then the right seat would be lined up about a foot to the right of the center.

Is that any clearer?
 
fiveoboy01 said:
Well then I wasn't lined up. Shrug.

Out of curiosity I looked at several videos and I do have a tendency to be left of centerline most of the time. I'll work on it:)
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I'm just a fount of useless information! :wink2:
 
Palmpilot said:
I understood him to be implying that the photographer's being in the right seat might be why the plane in his photo appears to be lined up on the left side of the runway.

I was trying to describe why that explanation wouldn't work: If the plane were actually perfectly lined up on the center of the runway, then the right seat would be lined up about a foot to the right of the center.

Is that any clearer?
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No...my "huh' wasn't aimed at a unclear explanation, rather it was aimed at logic I perceived to be flawed.

But maybe not.
 
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timwinters said:
No...my "huh' wasn't aimed at a unclear explanation, rather it was aimed at logic I perceived to be flawed.

But maybe not.
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If you still think my logic is flawed, can you explain why?
 
Tampico Trauma said:
Shoulda been flying this:
912ee279917612db05cc9d71e9e859d0.jpg



Sent from my iPhone using Tapatalk
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That's Gilbert Pierce's Clipper. I know it well and is is a work of art. He is based the next field over from me so I get to see it frequently.


Sent from my iPad using Tapatalk
 
FastEddieB said:
Best solution is to consciously try to put the centerline between your feet and keep it there. The plane may then touch down ever-so-slightly right of the centerline in a side-by-side configuration, but not enough to matter. In a tandem, of course, you're golden!
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Hmm, yeah if you do that you have the opposite effect as you already said. I'd rather be left of the centerline then right of it. I can see what's over on my side to the left, but if something is on the runway over the cowling to the right I can't. I don't wanna be going that way.

The way I was taught was to make sure the centerline lines up with your right foot (if left seat) or left foot (right seat).
 
Caramon13 said:
Hmm, yeah if you do that you have the opposite effect as you already said. I'd rather be left of the centerline then right of it. I can see what's over on my side to the left, but if something is on the runway over the cowling to the right I can't. I don't wanna be going that way.
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In a typical light airplane, the center of each seat is only a foot or so away from the center of the airplane. That's how much error will be attributable to the method he suggested, and it's FAR less than the centering errors that pilots often make.

The way I was taught was to make sure the centerline lines up with your right foot (if left seat) or left foot (right seat).
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I've seen that recommended for taxiing (using the knee instead of the foot), and it works in small aircraft because the distance from your eye to your foot (or knee) is roughly equal to the distance from your foot (or knee) to the pavement. When you're on final approach, those distances are very unequal, resulting in a far greater error than the method he suggested.
 
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