Why do pilots land at the thousand foot markers?

kicktireslightfires

kicktireslightfires

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kicktireslightfires
Why do pilots land at the thousand foot markers on a runway? What’s the rationale for not trying to land at the first available opportunity on the runway, which would be the numbers? Why overfly 1,000 feet of usable runway? I understand that the glide slope directs you down to that point, but why?
 
I'll take a stab at this. It's because of the distance between the eye level of the pilot and the bottom of the landing gear. In other words, the threshold crossing height is at eye level, not the bottom of the gear. Not a big deal in a Cessna or Piper but a big deal in larger turbine airplanes.
 
Larger a/c can’t use an aimpoint as close as smaller a/c or they’ll whack the gear on the ground before the runway.
 
kicktireslightfires said:
Why do pilots land at the thousand foot markers on a runway? What’s the rationale for not trying to land at the first available opportunity on the runway, which would be the numbers? Why overfly 1,000 feet of usable runway? I understand that the glide slope directs you down to that point, but why?
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Having the GS intercept the threshold would mean there is no margin for error on one side. You want Boeings and Airbuses landing in the dirt (or hitting the tail against a seawall) on a regular basis, that would be a good way to do it.
 
Because the runways, with fixed distance markers, aren't primary designed for the needs of light G.A. airplanes.

We aim for the 1,000' fixed distance markers and touchdown within the touchdown zone. This keep the 100'+ of airplane behind us from dragging through the approach lights/trees/obstacles if we are a bit lower than intended. There are some very short runways where we do intend to touchdown at the 1,000' point but they are special cases and usually special qualification airports.
 
kicktireslightfires said:
Why do pilots land at the thousand foot markers on a runway? What’s the rationale for not trying to land at the first available opportunity on the runway, which would be the numbers? Why overfly 1,000 feet of usable runway? I understand that the glide slope directs you down to that point, but why?
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For a Class D, C, and B airports.

Each pilot operating an airplane approaching to land on a runway served by a visual approach slope indicator must maintain an altitude at or above the glide path until a lower altitude is necessary for a safe landing
 
Clip4 said:
For a Class D, C, and B airports.

Each pilot operating an airplane approaching to land on a runway served by a visual approach slope indicator must maintain an altitude at or above the glide path until a lower altitude is necessary for a safe landing
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Seems odd that wouldn’t apply to any airport. What does if there’s a Tower or not have to do with the reasons to stay above the glide path.
 
Honestly, I believe it’s more for screwups than the anatomy of the plane. Given that you flare, you wouldn’t drag your gear before the runway if on glide slope and aiming for the end.

A non-flared approach, as in carrier AOA landings, another story.

While “disavowed”, airline guys “duck under” routinely. I’m with you, very little more useless than runway behind ya.

No matter what ya fly, you acclimate to where your feet are. Want the mains to touch in the middle of the numbers, generally no problem. BUT, every so often, just like a golfer or any other monkey skills sport, things just don’t go as planned. There’s quite a few tire marks pretty close to the end, despite aiming for 1000 feet AND flaring...
 
The normal glidepath (ILS or PAPI) is normally 3.00 degrees (+/- a bit). If one crosses the threshold at 50' that glidepath puts you 1000' down the runway. Transport category landing distance numbers are predicated on a stable approach on the glidepath. Landing further down the runway uses more runway than expected and landing below the glideslope is both unlawful in many cases, and risky. Part 121 and 135 operators are also required to uses only runways that have 1.67 times the required length when landing. Part 91 has no such restriction. If you are comfortable landing your light jet on 3000' runways, go for it. Take-off is a different can of worms.
 
When I fly, I typically aim to land on the numbers and fly a steeper approach than "glideslope indicated". But that was mostly because at the airport I trained it, that meant I could just turn off at the taxiway instead of having to backtaxi to get to it. :D
 
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luvflyin said:
Seems odd that wouldn’t apply to any airport. What does if there’s a Tower or not have to do with the reasons to stay above the glide path.
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Multiple runways and multiple pattern altitudes at some airports and a low altitude alert system for the approach.
 
Just for clarificartion...
Clip4 said:
For a Class D, C, and B airports.

Each pilot operating an [large or turbine powered] airplane approaching to land on a runway served by a visual approach slope indicator must maintain an altitude at or above the glide path until a lower altitude is necessary for a safe landing
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Edit…I misread this. The turbine airplane reg deals with electronic glide slope/glide path, and ends at the DA.


Arnold said:
Part 121 and 135 operators are also required to uses only runways that have 1.67 times the required length when landing.
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But like the Pirate’s Code, that’s really more of a guideline when it comes right down to it.
 
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luvflyin said:
Seems odd that wouldn’t apply to any airport. What does if there’s a Tower or not have to do with the reasons to stay above the glide path.
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It’s about noise…typically Class B, C, and D airports are surrounded by more population.
 
Because the turn off for my hanger is the last one on the most used runway.
I fly it the entire length of 24, land in the last 1,000 ft and taxi off.
Coming the other way, I land in the first 1,000 feet of 6 and exit.
If I have to land on 15 or 33 I just wander around, lost, until someone tells me where to go.
 
None of the above. Pilots of little airplanes that can't seem to stop wasting most of that 1000 feet might actually be aiming at the threshold. The round-out and flare alter that path, flattening it and carrying them farther down the runway. Even if they do it wrong, and don't do any round-out or flare until they're three feet off the surface, they'll float that 1000 feet anyway.

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Look at the trajectory at the far left, and where the airplane actually touches down well beyond the trajectory's intersection with the pavement. And this is a well-done landing; if the guy approaches too fast and doesn't flare until in ground effect, he'll easily float a thousand feet or more.

The only way you'll hit an aiming point is if you don't flare at all and crash it.
 
Fullerton has a 3,121' runway, with a 253' displaced threshold for 24.

The number of times someone hits the approach lighting located 307' *before* the start of the pavement is too damn high.

Some pilots suck at judging their touchdown point. Especially at night.
 
midlifeflyer said:
Heck, sometimes the 1000' markers make a landing too short.
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I'm a "on the numbers and first turn off guy" normally but with FDK's current taxiway construction on 23 that means a log taxi to the exit so stretching it out.
 
I always aim for the numbers in my bugsmasher unless the FBO is on the other end.

I was never taught to air for markers specifically so i simple go for numbers or the width stripes . Whatever is easier.

Most VASI PAPI will take you to the 1000 ft markers IIRC
 
Pugs said:
I'm a "on the numbers and first turn off guy" normally but with FDK's current taxiway construction on 23 that means a log taxi to the exit so stretching it out.
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The example I was thinking of is when leaving the runway at an early taxiway means blocking aircraft taxiing to the runway.
 
I like to watch the current crop of newbie air ambulance pilots landing the baby king air here. Seems they touchdown at least 1500-2000 feet down the runway. Runway length some 7300 feet so plenty of stopping area.

Personally, my Alaska experience taught me to be precisely on airspeed, no plus or minus and touch down at or within 10 feet of the threshold. Landing 1000 feet down the runway may only leave a few feet until off the runway, so I sorta got used to hitting the threshold.

It is hard for me to do a long landing, plus I like seeing my tire marks on the white line on the end of the pavement.
 
Not a Navy guy, but guessing the same reason you don’t try to snag the first wire.

Room for error or unforeseen circumstances (sheer??) is a good thing.
 
I agree with the others RE safety margin. If you aim for the piano keys and make that your 'spot' you don't give yourself too much margin. For a relatively standard 5K runway I would say that's a reasonable aiming point
 
Zeldman said:
I like to watch the current crop of newbie air ambulance pilots landing the baby king air here. Seems they touchdown at least 1500-2000 feet down the runway. Runway length some 7300 feet so plenty of stopping area.
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Which involves way more than just @Dan Thomas ’ illustration of touching down beyond the aiming point. Almost always excess speed, usually a fear of going to idle before touchdown, and both of these due to not having a clue where the wheels are—just hunting for the ground.

the most common reason I have jet pilots fail checkrides is for touchdown 3000-4000 feet down the runway when the ATP standard is 1000 ft markers -250’/+500’. Vref, 50’, thrust idle and it’s really difficult to miss the 1000 ft markers, much less the additional 750’ allowed.

of course, in my type we lose at least one airframe a year to landing overruns. (13 in the last 10 years that I’m aware of.)
 
MauleSkinner said:
It’s about noise…typically Class B, C, and D airports are surrounded by more population.
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Ah. I wouldn’t have thought they’d write that into the FAR’s 91.129-131 for that reason. Still kinda don’t make sense. Lotsa Class D’s revert to E or G at night. Even some C’s. The FAR explicitly refers to D ‘airspace.’ Seems at night after the Tower closed and everyone had grabbed there teddy bear and turned in for the night noise complaints would be more of an issue.
 
WDD said:
Taxpayers paid for all that concrete used for the runway. Why only use part of it?
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It is all available for use on takeoff. Landing is based on crossing the threshold with sufficient altitude to safely clear any obstacles. On a precision runway, the glideslope or glidepath intersects the pavement at roughly 1000 feet. For a runway that supports large aircraft, the landing gear is quite a bit lower than the pilot station. A typical threshold crossing height is 40 to 50 feet and the standard glideslope/path is 3 degrees.
 
danhagan said:
Landings on runways located on a Mesa-hilltop catch a lot less downdraft landing long (Catalina, Dona Ana NM, Sedona) ...
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Or in the lee of a Mesa/hills. The wind gods had me all puckered up going into Payson once up there near Sedona. I put her right on the numbers. Thank Gawd the numbers hadn’t been what I was aiming for.
 
luvflyin said:
Ah. I wouldn’t have thought they’d write that into the FAR’s 91.129-131 for that reason. Still kinda don’t make sense. Lotsa Class D’s revert to E or G at night. Even some C’s. The FAR explicitly refers to D ‘airspace.’ Seems at night after the Tower closed and everyone had grabbed there teddy bear and turned in for the night noise complaints would be more of an issue.
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That’s what I was told by a Fed…who also said it was a reg that was “forced on” the FAA.
 
danhagan said:
Landings on runways located on a Mesa-hilltop catch a lot less downdraft landing long (Catalina, Dona Ana NM, Sedona) ...
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Both ends of our home runway are built up from the surrounding area, and the runway is in a narrow valley with tree lined ridges down each side.

On a benign day I shoot for and land on the numbers, no sweat. But when the wind is whipping, we get all kinds of strange rotors and other effects and the wise pilot aims for the 1000ft markers, or even a little further on down if it's really whipping. Match the landing to the conditions.
 
Thanks all.

OK, so if you're landing an airliner, aim for the 1000' fixed distance markers (so you don't drag your big ass through the grass).

If you're landing a GA aircraft, aim for the numbers. (But if you're landing a GA aircraft at night, probably use the VASI/PAPI and aim for the 1000' fixed distance markers to ensure you don't hit anything.)

Do I have that right?
 
kicktireslightfires said:
Thanks all.

OK, so if you're landing an airliner, aim for the 1000' fixed distance markers (so you don't drag your big ass through the grass).

If you're landing a GA aircraft, aim for the numbers. (But if you're landing a GA aircraft at night, probably use the VASI/PAPI and aim for the 1000' fixed distance markers to ensure you don't hit anything.)

Do I have that right?
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I would normally aim past the numbers in a light GA airplane. I’d still touchdown before the 1000 ft markers, but reduce the chances of screwing up and hitting short.
 
kicktireslightfires said:
Thanks all.

OK, so if you're landing an airliner, aim for the 1000' fixed distance markers (so you don't drag your big ass through the grass).

If you're landing a GA aircraft, aim for the numbers. (But if you're landing a GA aircraft at night, probably use the VASI/PAPI and aim for the 1000' fixed distance markers to ensure you don't hit anything.)

Do I have that right?
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Not in my opinion

Salty said:
Well, if I'd been aiming for the 1,000 foot markers instead of the numbers when my engine went out, I might have made the field at least....
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