Landing on runways with a road before the threshold....

fiveoboy01

fiveoboy01

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Dirty B
I think we have all seen the video of the student in the 172 hitting the minivan.

Saturday was a perfect, calm day and I wanted to get some landing practice at 6P3 which is a 2200' x 30' runway. Normally I land on 50-150 foot wide strips but this will eventually be my "home" airport, so I have been practicing on it.

My brother caught some video, and while the approaches seemed pretty normal to me(and the 250+ hour pilot in the other seat), I am wondering if I'm too low over the road. I don't touch down on the displaced threshold, but do I need to adjust my approach here to be steeper and maybe touch down farther down the runway? I'm not sure if my height is an illusion on the video.. or I'm way too low. Sure didn't seem like it from above when I was coming in.

I did 7 landings here and they were all just like this one, save for one pretty high approach that had me touching down farther down the runway. Advice is appreciated, hitting a vehicle is NOT on my flying bucket list. Sorry for the grain, it was taken with a crummy cell phone.

https://www.youtube.com/watch?v=NGOd1gQUx_I
 
I know that gopros make you look a whole lot lower than you actually are. I always assumed that was because of the wide angle lens, but it could maybe be affecting your video too?
 
Had that fear at HHR (Hawthorne) for quite a while, until I forced myself to sit at the coffee shop and watch everyone else coming in.
 
Learn how to make power off approaches with full flap and minimum (short field) approach speed.

That's how you get (a) the steepest descent profile, and (b) the shortest ground run.

You should be able to land comfortably in half that 2200 feet in a 172 or similar, in no wind. Less than that if there is a headwind. Obviously, we don't want to test that regularly. :)

Test your stall speed at altitude to figure out your best approach speed. Unless you're at max gross, it will be less than the POH says.
 
pericynthion said:
Is there a stop sign? Do you watch for traffic?
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No stop sign but a prominently displayed sign on both sides of the road.

I do scan for traffic and the way the road is, it's easy to see vehicles in my peripheral vision. Cars and trucks are one thing, it's a side street so you don't see things like semi trucks on it very often but the possibility is there.

My brother said that other planes coming in have looked about the same, but that's him talking.
 
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MAKG1 said:
Learn how to make power off approaches with full flap and minimum (short field) approach speed.

That's how you get (a) the steepest descent profile, and (b) the shortest ground run.

You should be able to land comfortably in half that 2200 feet in a 172 or similar, in no wind. Less than that if there is a headwind. Obviously, we don't want to test that regularly. :)

Test your stall speed at altitude to figure out your best approach speed. Unless you're at max gross, it will be less than the POH says.
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I actually did a couple of power-out all the way at 45 degrees from the numbers and was able to easily bring it all the way in but I'm not sure if the approaches were any more steep.

30 degrees turning final, halfway down to the runway last notch to 40 degrees, 60-65 knots all the way down is how I was doing it.

The runway length definitely was not an issue for me. I was easily using half the distance or less to land and it was pretty much calm on the winds. Maybe putting it down a tad farther down than being too low over that road is a much better plan.
 
jpower said:
I know that gopros make you look a whole lot lower than you actually are. I always assumed that was because of the wide angle lens, but it could maybe be affecting your video too?
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Can't say for sure, but to me, up in the cockpit, I didn't think I was even close to being too low.

The location of that runway yes you're going to be "low" but there's a difference between a car driver being scared who might not know better, and actually being too low with the potential for an unsafe situation.
 
My guess, looking at the video, is you crossed the road with about 1/2 a wingspan of clearance (~18ft).

You should still be able to land with plenty of room to spare by using the numbers as the aim point, which should have you touch down another 300ft or so. It looks like you're using the beginning of the pavement as your aim point, and touching down just past the numbers.
 
fiveoboy01 said:
<snip>

30 degrees turning final, halfway down to the runway last notch to 40 degrees, 60-65 knots all the way down is how I was doing it.

<snip>.
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At what power setting?

When do you go to idle power?

Once you have cleared the road at a minimum altitude (say 25 or 50 feet) you should be at idle power. Seemed to me like you floated quite a bit further than I would have expected with full flaps and power off at 60-65 kts approach speed (perhaps a camera illusion).

If you have trouble making nice power off touchdowns try adding 5 or 10 kts to your approach speed.

Brian
CFIIG/ASEL
 
I wouldn't worry about the cars, if you can conquer the float, you'll feel better about coming in a little steeper. I never had a problem with a 172, but I float the Columbia 400 if I'm not right on the numbers. I will move the flaps from landing to takeoff position as I flare if I'm a little hot. Puts it down nicely. Have you experimented with pulling up to 30% as you flare?
 
With Cessna flaps on full you should be able to land further down with just a very little power on. I agree it's unsettling sometimes but with that length of runway you should be fine as stated before.
 
I go to a 2770 x 30 field to visit my parents, and in my "floating" Mooney I have no problem. There's a dirt road across one end and a paved road that comes close to the other end.

If you're worried about landing long, don't come in faster! Try calculating 1.3 * Vso. Memory says a 172 should stall around 45 knots; 45 * 1.3 = 59 knots. [Please correct the math if my memory is wrong.] You are targeting correctly, but the questions are two: 1) Vso is given at max gross; how much under gross are you landing? That will have a lower stall speed, so go slower. 2) How close are you to your target airspeed?

Planes will not land when going fast enough to fly, so they float in ground effect until the speed bleeds off. Go faster on final, and you will increase the length of your float. A Skyhawk, though, is pretty forgiving of this. Still try to not go faster.

For my plane, I reduce my speed on final by 5 mph for every 300 lbs below gross. Your airplane should have another number, similar but different. Maybe do some stall practice at different weights, then multiply by 1.3?

If you're comfortable with your landings, and aren't close to the other end, then don't worry about it. Just try not to go any faster.
 
brcase said:
At what power setting?
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1700-1800 abeam, and adjust power from there. Honestly I don't watch the tach, I'm busy watching the airspeed and sight picture and I adjust the power to compensate. Turn base around 75-80, final 65-70(which I now see might be a little fast).

When do you go to idle power?
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Again depends on the approach but for this airport here I'd say about over the road is where I pull the engine to idle.

The guy that mentioned my aim point might be onto something, I'm aware of the displaced threshold but maybe I'm subconsciously aiming for the wrong spot. Next time I'll move the aim point forward a little. I'm not concerned about running out of runway, as it's easy to tell if I've gobbled up too much before touchdown... that results in a go-around. I'm mainly concerned about being too low and cars on the road.

Using the weight numbers in the manual, with myself and my passenger and full fuel we were about 290# under gross weight. I want to say I wasn't going any slower than 65 on final so next time I'll get it down to 60. Should be easily doable with full flaps even if the approach is a bit steeper.

If VSo is 41, then 1.3 is 53.3 knots, so being significantly under gross, 55 would be safe in theory. But I'd probably try some slow flight at altitude just to get a better feel for the handling characteristics.

The weird thing is that the manual says 60 for short field technique, and 55-65 for a normal landing.

I've only got 73 hours and 235 landings so still in the practice phase. Just want to be safe, that's mainly it. I appreciate the responses:)
 
fiveoboy01 said:
I think we have all seen the video of the student in the 172 hitting the minivan.

Saturday was a perfect, calm day and I wanted to get some landing practice at 6P3 which is a 2200' x 30' runway. Normally I land on 50-150 foot wide strips but this will eventually be my "home" airport, so I have been practicing on it.

My brother caught some video, and while the approaches seemed pretty normal to me(and the 250+ hour pilot in the other seat), I am wondering if I'm too low over the road. I don't touch down on the displaced threshold, but do I need to adjust my approach here to be steeper and maybe touch down farther down the runway? I'm not sure if my height is an illusion on the video.. or I'm way too low. Sure didn't seem like it from above when I was coming in.

I did 7 landings here and they were all just like this one, save for one pretty high approach that had me touching down farther down the runway. Advice is appreciated, hitting a vehicle is NOT on my flying bucket list. Sorry for the grain, it was taken with a crummy cell phone.

https://www.youtube.com/watch?v=NGOd1gQUx_I
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fiveoboy01 said:
Just for S&G, here is the high approach I mentioned in the first post. My brother doesn't capture it in the video but clearance over the road was a lot more. I also landed much farther down the runway, probably 1/3 of the way down or a bit more.

https://www.youtube.com/watch?v=PLplecQTRV0&list=UUZ-tdB5Cg291M5LKk9Jd-lQ
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Speed seems higher than normal. If you need to get comfortable with short field landings get a CFI to work with you on the low end of vs. My CFI took me in a 172 to 2w2 in MD which has an 1800 ft runway only after I proved to him I could hit the numbers at 55kts repeatedly. Did three landings there all of which were go pro's.

You looked low (flat) which can lead to carrying some speed you don't want. Its very possible to short field with a much steeper decent AND lower groundspeed.

Did you feel like you were shallow on landing? This last video was steeper however you came in idle which tells me you were fast too (you can see some float I'm round out). Trim for 55 kts and use power to decide when and where the wheels kiss the ground.


Sent from my Nexus 7 using Tapatalk
 
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If you're talking about the first video, all but 1 landing was just like that and it didn't feel out of the ordinary. I might have been 5 knots too fast but other than that, they felt like a normal approach and landing... then when I saw the video I started to wonder if I was too low and needed to steepen it up slightly. The guy right seat has landed there plenty of times and he didn't really say much in the way of floating or coming in flat.

Keep in mind there was no wind so groundspeed was up compared to what it might be otherwise.

I think a trip up with my CFI might be in order just to practice some slow/steeper approaches even if it's at MSN with its 150 foot wide runways.
 
Were you flying around 9am? I think I saw you.
 
Took off from MSN at 8, direct to Waunakee for a few landings, then stopped, got out because my PAX wanted to talk to a couple of guys there and I wanted to stretch my legs. Took back off and I think did 4 more before going back to Madison. Maybe an hour and a half total.

Haven't seen such a perfect day for flying since last summer here.
 
Years ago at my airport, 2200 feet paved. Tri pacer landing, dirt road at end of runway, leads to farm. Farmer in pickup , not watching for aircraft driving out road. Tripacer hits truck with landing gear, turns truck over, tripacer goes onto runway, wings messed up , leaking gas. Both get out without any real injury and no fire. Miracle. Tripacer pilot had been test pilot at Martin on the Martin marauder during WW 2.
 
I am based out of the field where the plane hit the SUV

See and avoid.

I see cars on that road when I am on final and I don't change my glide to accommodate them. I am always ready to go around as anyone should be.

Only thing that ever rattled me was a fence on the edge of that little road. some teens (read: Idiots) were partying out there and they were standing up on the fence just after sunset.

It was as if they were hoping to reach up and touch a wheel of a landing plane or something.

I grumbled to myself. "I am going to land this plane and if I give someone a Darwin award in the process, So be it."
 
Bryan, you DO know about the "secret switch" on all Socata's that deploys the 20mm cannon right? :)

Jeff
TB10
 
fiveoboy01 said:
Using the weight numbers in the manual, with myself and my passenger and full fuel we were about 290# under gross weight. I want to say I wasn't going any slower than 65 on final so next time I'll get it down to 60. Should be easily doable with full flaps even if the approach is a bit steeper.
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This is a 172? The POH says 61 KIAS for a short field, and that's at max gross.

Go to altitude and measure the stall speed at idle with full flap. Convert to CAS, multiply by 1.3, then convert back to IAS. The correction is big for all 172s near stall, and really big for SPs, so you will get wrong answers if you just multiply IAS.

It's fun -- and quite possible at that weight -- to practice slow flight below the white arc.
 
I think you would clear a car, but it looks close. Our local airpark has sign warning drivers of planes, but that doesn't mean people actually check.
 
fiveoboy01 said:
1700-1800 abeam, and adjust power from there. Honestly I don't watch the tach, I'm busy watching the airspeed and sight picture and I adjust the power to compensate. Turn base around 75-80, final 65-70(which I now see might be a little fast).



Again depends on the approach but for this airport here I'd say about over the road is where I pull the engine to idle.

The guy that mentioned my aim point might be onto something, I'm aware of the displaced threshold but maybe I'm subconsciously aiming for the wrong spot. Next time I'll move the aim point forward a little. I'm not concerned about running out of runway, as it's easy to tell if I've gobbled up too much before touchdown... that results in a go-around. I'm mainly concerned about being too low and cars on the road.

Using the weight numbers in the manual, with myself and my passenger and full fuel we were about 290# under gross weight. I want to say I wasn't going any slower than 65 on final so next time I'll get it down to 60. Should be easily doable with full flaps even if the approach is a bit steeper.

If VSo is 41, then 1.3 is 53.3 knots, so being significantly under gross, 55 would be safe in theory. But I'd probably try some slow flight at altitude just to get a better feel for the handling characteristics.

The weird thing is that the manual says 60 for short field technique, and 55-65 for a normal landing.

I've only got 73 hours and 235 landings so still in the practice phase. Just want to be safe, that's mainly it. I appreciate the responses:)
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That is what it looked like to me, that you were a just a little bit fast on your touch down. If you are looking for a steeper approach use the 60kts (per your POH) on short final (before you get to the road). The preference is usually to be power off, but you might find that you need to carry a bit of power into the flare at that low of a speed. That is where the practice comes in.
 
Runway 27 has a displaced threshold, but they didn't displace it very much:

aerial photo


It's about 180' from the threshold to the street. If you use that threshold as an aiming point for a 3 degree glide slope, you would cross the road at just 9' 5" AGL.

Light trucks are about 7 feet high. Semis about 13 feet.

A collision with a truck looks like it could definitely happen if you use that threshold marker as an aiming point.

Maybe if you use a different aiming point, like the middle of the first lawn, you might have a decent margin when you cross the street. But would that leave you enough runway to land?
 
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That depends on a lot of variables but generally I'd say yes you could do that and have enough runway.

Also looks like part of the equation is to come in steeper than 3 degrees.
 
1st of several images: 1948' gravel over turf. #32 is on this end, near the bay. #14 is at the top, just this side of the trees and the country road, and beside the little brown club house. See Image #2 to follow.

HR
 

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Lawreston said:
1st of several images: 1948' gravel over turf. #32 is on this end, near the bay. #14 is at the top, just this side of the trees and the country road, and beside the little brown club house. See Image #2 to follow.

HR
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huh??
 
Image #2 of several. About to pass over #32. #14 (Upper, near trees) is Left Pattern but this was a photo op, not a landing approach. See Image #3 to follow. (I wish my Skyhawk has an opening right window like this C-150 did.)

HR
 

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Image #3. #14 can be seen upper left center; also note how close the tree line is to the highway and the beginning of #14. See Image #4 to follow.

HR
 

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Image #4: Low approach/fly-by on #14. No landing because it was early April; previous three weeks of snow, rain, melt, freeze, melt; annual too soggy conditions on the ground. 08B Merrymeeting Airport, Bowdoinham, Maine.
Yes, that's a "launch pad" straight ahead: annual frost heave over where a trenched pipeline runs across the strip, servicing houses which have been built at the edges. If roll-out is too fast it'll cause a short launch.

HR
 

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fiveoboy01 said:
That depends on a lot of variables but generally I'd say yes you could do that and have enough runway.

Also looks like part of the equation is to come in steeper than 3 degrees.
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There is nothing special about 3 deg unless you're driving an airliner.

If you're concerned about obstructions, make the approach as steep as you can.

If you're REALLY concerned about obstructions, you can slip over them and straighten out for touchdown. Though it takes some practice to do that under 20 AGL. I don't think you need to go to that extreme here.
 
When I was based at Merrymeeting, this tie-down area is what used to be the runway. When the powerlines went through the runway was moved to be 14/32(previous photos) instead of whatever it used to be. When we leave #14, at about 400' we're passing over the powerlines and will be out over Merrymeeting Bay(the largest natural waterfowl breeding grounds east of the Missisippi River). Before a developer got permission to build houses in the airport area, archeological digs were done because the area was once Native American territory and, allegedly, there's an underground tunnel which would allow the "Natives" to escape to the sea if threatened by the "white people."

HR
 

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MAKG1 said:
There is nothing special about 3 deg unless you're driving an airliner.
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Yep. I know that most of my approaches(even with no obstacles to clear) are steeper than that.

I don't think you need to go to that extreme here.
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Definitely not. I think steepening it slightly and moving my aim point forward just a bit will take care of this. The videos(s) shows there is room for a car under me, but a little more room would make me more comfortable.
 
Hank S said:
If you're worried about landing long, don't come in faster! Try calculating 1.3 * Vso. Memory says a 172 should stall around 45 knots; 45 * 1.3 = 59 knots. [Please correct the math if my memory is wrong.] You are targeting correctly, but the questions are two: 1) Vso is given at max gross; how much under gross are you landing? That will have a lower stall speed, so go slower. 2) How close are you to your target airspeed?

For my plane, I reduce my speed on final by 5 mph for every 300 lbs below gross. Your airplane should have another number, similar but different. Maybe do some stall practice at different weights, then multiply by 1.3?
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The formula, which works for any airplane, is this:

Speed to adjust in KCAS * SQRT(Actual weight / Max Gross Weight) = Adjust speed in KCAS.

This works for many speeds - Stall speeds, landing speeds, etc. Let's look at this particular situation. You're flying a 172N. The POH specifies full 40º flaps and 60 KIAS for a short field landing. At that flap setting, 60 KIAS = 62 KCAS. Your max gross weight is 2300 pounds, and you were at about 2000 pounds (I'm sure you burned 10 pounds of fuel going from MSN-6P3, probably more). So, 62*SQRT(2000/2300) = 57.8 KCAS, or 54 KIAS.

Try your next approaches flying final at 54 KIAS, and you'll end up with a lot more room in front of you after landing and less float. :thumbsup:

fiveoboy01 said:
The guy right seat has landed there plenty of times and he didn't really say much in the way of floating or coming in flat.
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Were you flying with Scott L? If so, I'm sure he told you he's looking for someone to rent his house on the north side of the runway (I think he bought a house on the south side). If not... Want to rent a house on an airport? :D

I think a trip up with my CFI might be in order just to practice some slow/steeper approaches even if it's at MSN with its 150 foot wide runways.
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I like doing short-fields on 32 at MSN - If you make the turnoff on taxiway E without having to back-taxi, you did a good one. :yes:
 
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