Piper clips semi trailer on short final...

fiveoboy01

fiveoboy01

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Dirty B
...both occupants ok.

http://www.wkow.com/story/31125003/2016/02/02/plane-clips-semi-in-racine-county

Runway 26 has a PAPI...

Aerial view:

sylvania-XL.jpg
 
I don't know what kind of plane that was, but I can put my Piper down in 600 ft. If you need all 2300 you're either very bad at managing power, or have a plane that really shouldn't be landing on short strips.
 
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.
 
Caramon13 said:
I don't know what kind of plane that was, but I can put my Piper down in 600 ft. If you need all 2300 you're either very bad at managing power, or have a plane that really shouldn't be landing on short strips.
Click to expand...

The video shows a picture and it looks like N1678J which is a Cherokee 140 registered in IL.
 
Surely sounds like the pilot was dragging it in. No need for this plane to have been that low on short final.

I have taken an Archer II in and out of Marlboro, MA (9B1), a 1659 foot strip. That does not make me a hero; lots of folks take their initial training at Marlboro.

-Skip
 
Skip Miller said:
Surely sounds like the pilot was dragging it in. No need for this plane to have been that low on short final.

I have taken an Archer II in and out of Marlboro, MA, a 1659 foot strip.
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I wonder if this was at night? The picture in the video looked rather dark.

The PAPI exists for a reason.
 
It always puzzles me that some pilots seem to think that landing short requires to drag the plane in. Being low, slow and behind the power curve is certainly a quite undesirable comination... :rolleyes:
 
Yeah... And you GA pilots still think landing on the numbers is the correct way to do it...
Threshold 50', touchdown 1,000' down. That is correct, true, tried, and tested.
 
Landing on my dad's ag strip 1980.

0adc3856ceede26ab382490e1e717d46.jpg



Jim R
Collierville, TN

N7155H--1946 Piper J-3 Cub
N3368K--1946 Globe GC-1B Swift
N4WJ--1994 Van's RV-4
 
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N3368K said:
Landing on my dad's ag strip 1980.

0adc3856ceede26ab382490e1e717d46.jpg



Jim R
Collierville, TN

N7155H--1946 Piper J-3 Cub
N3368K--1946 Globe GC-1B Swift
N4WJ--1994 Van's RV-4
Click to expand...
*IF* that's a similar case, than that just shows how effed up GA is and why the stats show it dangerous.
Most here bring UP those stats from jackasses like that.
 
It was a local flying club plane. Reminded me that a student pilot did nearly the same thing at the same airport when I 1st started flying:

PA28 vs Semi 1997

She wasn't nearly as lucky.

BE CAREFUL OUT THERE FRIENDS!
 
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Here's a video of me landing at said similar airport. Notice my height over the road:

http://youtu.be/zH0udhQKguw

The interstate near the accident airport is about 1000 feet from the runway... No reason to be that low, that far out.

And someone said 50 feet over the threshold and touch down at the 1000 foot mark... That doesn't work at every airport. I'd have a hair over 1000 feet left in the example video above if I touched down that far down the runway.
 
Kritchlow said:
Yeah... And you GA pilots still think landing on the numbers is the correct way to do it...
Click to expand...

I don't. That eats up safety margin.

On the other hand...

Threshold 50', touchdown 1,000' down. That is correct, true, tried, and tested.
Click to expand...

Touching down that far down a 2400 foot runway eats up safety margin on the other end.
 
Gas ... check
Undercarriage ... check
Mixture ... check
Prop ... check
Seat belts ... check
Semi ... check
 
Palmpilot said:
I don't. That eats up safety margin.

On the other hand...



Touching down that far down a 2400 foot runway eats up safety margin on the other end.
Click to expand...

I can't open any link you may haven posted, but... If you use landing over 50' obstacle numbers that's where you're at. That's where all numbers are calculated includiding ILS numbers.
 
Kritchlow said:
I can't open any link you may haven posted, but... If you use landing over 50' obstacle numbers that's where you're at. That's where all numbers are calculated includiding ILS numbers.
Click to expand...

Which is probably one reason why Palo Alto Airport doesn't have an ILS.

By the way, I didn't post any links.
 
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Kritchlow said:
I can't open any link you may haven posted, but... If you use landing over 50' obstacle numbers that's where you're at. That's where all numbers are calculated includiding ILS numbers.
Click to expand...


Not every airport has an ILS and a 10,000 foot runway and we aren't all piloting a Boeing.
 
That airport's threshold is displaced for a reason. This pilot was simply flying his approach too low.

Take a look at Dallas Airpark (F69) - same concept. They displaced that threshold to keep people from colliding with a vehicle or, more likely, the QuikTrip sign across the street.

The short field landing technique of almost all airplanes is designed to allow a landing over a 50' obstacle. It is a steeper, not shallower, approach angle.

But even a normal approach with full flaps at any of these airports would not require an approach angle that would clip a semi on the interstate - barring something abnormal like an electrical failure that precludes flap extension.

This is why we can't have nice things.
 
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Same deal with Watts Woodland airport (O41). Its pretty intimidating seeing cars, let alone large trucks drive by on the road on final. But as long as you respect the displaced threshold, you're actually fairly high above them unless you go ridiculously shallow.
 
Kritchlow said:
*IF* that's a similar case, than that just shows how effed up GA is and why the stats show it dangerous.
Most here bring UP those stats from jackasses like that.
Click to expand...

It was a rural ag strip a bit under 2000'. At one time had up to three a/c working from it. Stearman, SuperCubs, Pawnees and Thrushes.

There was little traffic with excellent visibility both directions of the road. Maybe not someplace lots of people would want to land, but where many folks learned to fly. Even at that low altitude, the touchdown was likely another couple hundred feet beyond. There were never any accidents there other than one guy catching the highline wire which was strung across the end years before this picture.

If it makes you feel better that strip is long since gone.
 
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I took a screen shot from google maps. It is about 350' from the end of the displaced threshold to the interstate (see thumbnail). I would imagine most trailers are in the neighborhood of 15 to 16 feet tall. A 3 degree glide path would put you just over 18 feet above the ground. (tan (3) x 350' = 18.3') That seems to be cutting it WAY to close.

Did I do something wrong there?
 
Kritchlow said:
Yeah... And you GA pilots still think landing on the numbers is the correct way to do it...
Threshold 50', touchdown 1,000' down. That is correct, true, tried, and tested.
Click to expand...

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.
 
FredFenster said:
13' 6" is the legal height limit in WI, so it was that or less..
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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...
 
Az, I'm pretty sure I'm not 18 feet above the ground 350 from the runway. That's WAY too low.

Assuming I want to be about 10 feet above the threshold (with no obstacles), that means I would have to be dragging it in almost 300 feet.

At an approach speed of 55 knots in my plane I don't think it would be unreasonable to be at 50-100 ft or more altitude-wise that far out. There's no good reason to be that flippin' low.

I don't have to do any fancy math, it's just rational thinking. I would be at 18 feet above the threshold, but straight and level at 18 feet for 350 feet distance?
 
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Sac Arrow said:
But as long as you respect the displaced threshold, you're actually fairly high above them unless you go ridiculously shallow.
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Some pilots take a 'stabilized approach' to the extreme. I see it all the time unfortunately.
 
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.
 
Caramon13 said:
Az, I'm pretty sure I'm not 18 feet above the ground 350 from the runway. That's WAY too low.

Assuming I want to be about 10 feet above the threshold (with no obstacles), that means I would have to be dragging it in almost 300 feet.

At an approach speed of 55 knots in my plane I don't think it would be unreasonable to be at 50-100 ft or more altitude-wise that far out. There's no good reason to be that flippin' low.

I don't have to do any fancy math, it's just rational thinking. I would be at 18 feet above the threshold, but straight and level at 18 feet for 350 feet distance? Are you kidding?
Click to expand...

I completely agree with you. I just obsess over numbers and math. I know I did something wrong in my calculating. I am just trying to figure out what it was that I did wrong.

I agree that being 18 feet above the ground 350 feet from the runway is far too low.
 
azpilot said:
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...
Click to expand...

Most people don't touch down on the threshold, and many use a steeper glide angle than 3 degrees. The pilot in question was well under a 3 degree glide slope.
 
Croomrider said:
Most people don't touch down on the threshold, and many use a steeper glide angle than 3 degrees. The pilot in question was well under a 3 degree glide slope.
Click to expand...

Yeah and don't forget that 3 degree glide slopes are for approaches that put you down 1000 ft from the threshold in most cases.

I was watching a video I did of a landing into KPGD and while I don't really trust the GPS accuracy I was between an 8-10 degree angle. That's probably wrong, but I put it down just past the numbers and made it 600 ft before turning off to a taxiway.
 
The 18.3' calculation for a 3 degree slope at 350' from touchdown point is accurate, so the 3 degree slope and the 350' estimate are the assumptions that can be challenged.
 
It's a long day at the office when I read the thread title as "Paper Clips"
 
I've flown in and out of this airport many times. Besides the hwy and the length of the runway it is a very active parachuting airport too so it can be exciting coming in and out at times. I always feel close to the hwy I94 (major interstate between Chicago and Milwaukee) on landing but never like I was close enough to clip anything. The length isn't an issue for me so this is one airport I'm very careful not to drag it in.
 
azpilot said:
I completely agree with you. I just obsess over numbers and math. I know I did something wrong in my calculating. I am just trying to figure out what it was that I did wrong.

I agree that being 18 feet above the ground 350 feet from the runway is far too low.
Click to expand...

The math is right, but 3 deg is shallow. Draw out a 3 deg angle and you'll see there's not much divergence. As others have pointed out, you shouldn't target the threshold on a 3* glideslope. The threshold crossing height isn't expected to be zero.
 
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...
Click to expand...

Did you assume touchdown on the threshold? I don't touch down there.
 
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