Why not make the touchdown zone of runways wider than the rest?
Multi tool use
$begingroup$
Reasons:
- Save money by making the rest of the runway narrower
- Larger margin of error left and right
- Easier to turn around, if necessary
And if the reason that it isn't done is merely for regulation/legal reasons: Is this something that would be practical if it were allowed?
runways
asked Jan 14 at 8:05
dtgqdtgq
15714
$endgroup$
|
show 2 more comments
$begingroup$
Reasons:
- Save money by making the rest of the runway narrower
- Larger margin of error left and right
- Easier to turn around, if necessary
And if the reason that it isn't done is merely for regulation/legal reasons: Is this something that would be practical if it were allowed?
runways
asked Jan 14 at 8:05
dtgqdtgq
15714
$endgroup$
18
$begingroup$
It sounds like the underlying assumption is that it is easier to stay centered after touchdown. I think that might not be true, crosswind and e.g. uneven braking power can be problematic even after the wheels are already on the ground.
$endgroup$
– jpa
Jan 14 at 10:26
7
$begingroup$
Consider the same question phrased a different way could we make some parts of the runway narrower than the rest?, and you'll probably come up with quite a few counter-arguments.
$endgroup$
– Toby Speight
Jan 14 at 13:19
13
$begingroup$
How would it give you a larger margin of error? It's no use having a wide touchdown zone if you're then going to go off the runway as it narrows.
$endgroup$
– Dan Hulme
Jan 14 at 17:22
2
$begingroup$
@dtgq What problem are you trying to solve? Planes running off runways is pretty rare.
$endgroup$
– zeta-band
Jan 15 at 0:15
1
$begingroup$
"if you touch down off the side of the runway" then you've screwed up badly and should have gone around.
$endgroup$
– Roger Lipscombe
Jan 15 at 11:49
|
show 2 more comments
$begingroup$
Reasons:
- Save money by making the rest of the runway narrower
- Larger margin of error left and right
- Easier to turn around, if necessary
And if the reason that it isn't done is merely for regulation/legal reasons: Is this something that would be practical if it were allowed?
runways
asked Jan 14 at 8:05
dtgqdtgq
15714
$endgroup$
Reasons:
- Save money by making the rest of the runway narrower
- Larger margin of error left and right
- Easier to turn around, if necessary
And if the reason that it isn't done is merely for regulation/legal reasons: Is this something that would be practical if it were allowed?
runways
runways
asked Jan 14 at 8:05
dtgqdtgq
15714
asked Jan 14 at 8:05
dtgqdtgq
15714
asked Jan 14 at 8:05
dtgqdtgq
15714
asked Jan 14 at 8:05
dtgqdtgq
15714
asked Jan 14 at 8:05
dtgqdtgq
15714
15714
18
$begingroup$
It sounds like the underlying assumption is that it is easier to stay centered after touchdown. I think that might not be true, crosswind and e.g. uneven braking power can be problematic even after the wheels are already on the ground.
$endgroup$
– jpa
Jan 14 at 10:26
7
$begingroup$
Consider the same question phrased a different way could we make some parts of the runway narrower than the rest?, and you'll probably come up with quite a few counter-arguments.
$endgroup$
– Toby Speight
Jan 14 at 13:19
13
$begingroup$
How would it give you a larger margin of error? It's no use having a wide touchdown zone if you're then going to go off the runway as it narrows.
$endgroup$
– Dan Hulme
Jan 14 at 17:22
2
$begingroup$
@dtgq What problem are you trying to solve? Planes running off runways is pretty rare.
$endgroup$
– zeta-band
Jan 15 at 0:15
1
$begingroup$
"if you touch down off the side of the runway" then you've screwed up badly and should have gone around.
$endgroup$
– Roger Lipscombe
Jan 15 at 11:49
|
show 2 more comments
18
$begingroup$
It sounds like the underlying assumption is that it is easier to stay centered after touchdown. I think that might not be true, crosswind and e.g. uneven braking power can be problematic even after the wheels are already on the ground.
$endgroup$
– jpa
Jan 14 at 10:26
7
$begingroup$
Consider the same question phrased a different way could we make some parts of the runway narrower than the rest?, and you'll probably come up with quite a few counter-arguments.
$endgroup$
– Toby Speight
Jan 14 at 13:19
13
$begingroup$
How would it give you a larger margin of error? It's no use having a wide touchdown zone if you're then going to go off the runway as it narrows.
$endgroup$
– Dan Hulme
Jan 14 at 17:22
2
$begingroup$
@dtgq What problem are you trying to solve? Planes running off runways is pretty rare.
$endgroup$
– zeta-band
Jan 15 at 0:15
1
$begingroup$
"if you touch down off the side of the runway" then you've screwed up badly and should have gone around.
$endgroup$
– Roger Lipscombe
Jan 15 at 11:49
18
18
$begingroup$
It sounds like the underlying assumption is that it is easier to stay centered after touchdown. I think that might not be true, crosswind and e.g. uneven braking power can be problematic even after the wheels are already on the ground.
$endgroup$
– jpa
Jan 14 at 10:26
$begingroup$
It sounds like the underlying assumption is that it is easier to stay centered after touchdown. I think that might not be true, crosswind and e.g. uneven braking power can be problematic even after the wheels are already on the ground.
$endgroup$
– jpa
Jan 14 at 10:26
7
7
$begingroup$
Consider the same question phrased a different way could we make some parts of the runway narrower than the rest?, and you'll probably come up with quite a few counter-arguments.
$endgroup$
– Toby Speight
Jan 14 at 13:19
$begingroup$
Consider the same question phrased a different way could we make some parts of the runway narrower than the rest?, and you'll probably come up with quite a few counter-arguments.
$endgroup$
– Toby Speight
Jan 14 at 13:19
13
13
$begingroup$
How would it give you a larger margin of error? It's no use having a wide touchdown zone if you're then going to go off the runway as it narrows.
$endgroup$
– Dan Hulme
Jan 14 at 17:22
$begingroup$
How would it give you a larger margin of error? It's no use having a wide touchdown zone if you're then going to go off the runway as it narrows.
$endgroup$
– Dan Hulme
Jan 14 at 17:22
2
2
$begingroup$
@dtgq What problem are you trying to solve? Planes running off runways is pretty rare.
$endgroup$
– zeta-band
Jan 15 at 0:15
$begingroup$
@dtgq What problem are you trying to solve? Planes running off runways is pretty rare.
$endgroup$
– zeta-band
Jan 15 at 0:15
1
1
$begingroup$
"if you touch down off the side of the runway" then you've screwed up badly and should have gone around.
$endgroup$
– Roger Lipscombe
Jan 15 at 11:49
$begingroup$
"if you touch down off the side of the runway" then you've screwed up badly and should have gone around.
$endgroup$
– Roger Lipscombe
Jan 15 at 11:49
|
show 2 more comments
3 Answers
3
active
oldest
votes
$begingroup$
Because most runways already are as narrow as safely feasible.
Let us look at your question piece by piece:
Save money by making the rest of the runway narrower
You seem to be assuming we are currently deliberately wasting asphalt on making runways wider than needed, and could build them narrower. As they say on Wikipedia: [citation needed].
Larger margin of error left and right
The touchdown zone is the whole runway, as long as the aircraft in question can stop afterwards, so if you start down this alley you'll find it cheaper to complete the runway in the same width.
Easier to turn around, if necessary
This is already done by including turn pads, on top of the nominal width. For an example, see: OGZ
edited Jan 14 at 20:08
Loong
266214
answered Jan 14 at 8:45
AEhereAEhere
1,455417
$endgroup$
add a comment |
$begingroup$
Because planes that landed towards the edge of the touch-down zone would run off the side of the runway when it narrowed.
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
$endgroup$
1
$begingroup$
That's (one of the reasons) why we have rudders and tillers - so that planes touching down off-center can be steered back to the centerline.
$endgroup$
– Sean
Jan 15 at 4:04
$begingroup$
@Sean and those aren't too effective until speed drops significantly for ground handling.
$endgroup$
– jwenting
Jan 15 at 6:28
14
$begingroup$
@Sean To provide enough time to slow so you can steer back safely, you'd probably need half the runway to be full-width and the second half could be tapered off. But that second half is the first half of the opposite-direction runway, so it has to be full-width too.
$endgroup$
– Dan Hulme
Jan 15 at 9:44
add a comment |
$begingroup$
At least a few runways are divided by length. For example, once at Boeing Field (BFI) four general aviation light aircraft were cleared to land approximately at once on two runways. My VFR landing clearance was to land in the first half of runway 14R while another aircraft above and slightly ahead of me had to stay at 500 AGL(? I forget the exact number) until the threshold and then land on the second half. The left runway had something similar occurring at about the same time.
Having irregular width runways doesn't help this much. Also it is difficult to imagine that the non-ends would be graded any differently. In the overall project of constructing a runway, it is highly likely that the land preparation, utilities, and grading are like 80% of the cost of the surface. A forum exchange breakdown of a Canadian 7000 x 100 foot runway is:
$ 250,000 geotechnical analysis
$ 4,000,000 gravel (60 cm of 7.5 cm minus, 25 cm 1 cm minus)
$ 2,500,000 labor and equipment rental
$ 100,000 quality testing (compaction, etc.)
$ 2,000,000 asphalt (15 cm)
$ 200,000 lighting
$ 10,000 painted markings
----------
$ 9,060,000 total
Would making the shape narrower increase any of those costs? Probably. Certainly less materials should decrease the overall cost, and maybe labor could be economized.
For strong crosswind landings, I usually use all of whatever width there is!
answered Jan 15 at 0:25
wallykwallyk
23915
$endgroup$
2
$begingroup$
Interesting mixture of units. Runway area in feet and depth in centimetres :-)
$endgroup$
– uɐɪ
Jan 15 at 11:33
1
$begingroup$
@uɐɪ So volume is in square feet centimetres!
$endgroup$
– Oscar Bravo
Jan 15 at 14:12
1
$begingroup$
Similar thing happens at Oshkosh every year, right?
$endgroup$
– yshavit
Jan 15 at 16:06
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "528"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faviation.stackexchange.com%2fquestions%2f59049%2fwhy-not-make-the-touchdown-zone-of-runways-wider-than-the-rest%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Because most runways already are as narrow as safely feasible.
Let us look at your question piece by piece:
Save money by making the rest of the runway narrower
You seem to be assuming we are currently deliberately wasting asphalt on making runways wider than needed, and could build them narrower. As they say on Wikipedia: [citation needed].
Larger margin of error left and right
The touchdown zone is the whole runway, as long as the aircraft in question can stop afterwards, so if you start down this alley you'll find it cheaper to complete the runway in the same width.
Easier to turn around, if necessary
This is already done by including turn pads, on top of the nominal width. For an example, see: OGZ
edited Jan 14 at 20:08
Loong
266214
answered Jan 14 at 8:45
AEhereAEhere
1,455417
$endgroup$
add a comment |
$begingroup$
Because most runways already are as narrow as safely feasible.
Let us look at your question piece by piece:
Save money by making the rest of the runway narrower
You seem to be assuming we are currently deliberately wasting asphalt on making runways wider than needed, and could build them narrower. As they say on Wikipedia: [citation needed].
Larger margin of error left and right
The touchdown zone is the whole runway, as long as the aircraft in question can stop afterwards, so if you start down this alley you'll find it cheaper to complete the runway in the same width.
Easier to turn around, if necessary
This is already done by including turn pads, on top of the nominal width. For an example, see: OGZ
edited Jan 14 at 20:08
Loong
266214
answered Jan 14 at 8:45
AEhereAEhere
1,455417
$endgroup$
add a comment |
$begingroup$
Because most runways already are as narrow as safely feasible.
Let us look at your question piece by piece:
Save money by making the rest of the runway narrower
You seem to be assuming we are currently deliberately wasting asphalt on making runways wider than needed, and could build them narrower. As they say on Wikipedia: [citation needed].
Larger margin of error left and right
The touchdown zone is the whole runway, as long as the aircraft in question can stop afterwards, so if you start down this alley you'll find it cheaper to complete the runway in the same width.
Easier to turn around, if necessary
This is already done by including turn pads, on top of the nominal width. For an example, see: OGZ
edited Jan 14 at 20:08
Loong
266214
answered Jan 14 at 8:45
AEhereAEhere
1,455417
$endgroup$
Because most runways already are as narrow as safely feasible.
Let us look at your question piece by piece:
Save money by making the rest of the runway narrower
You seem to be assuming we are currently deliberately wasting asphalt on making runways wider than needed, and could build them narrower. As they say on Wikipedia: [citation needed].
Larger margin of error left and right
The touchdown zone is the whole runway, as long as the aircraft in question can stop afterwards, so if you start down this alley you'll find it cheaper to complete the runway in the same width.
Easier to turn around, if necessary
This is already done by including turn pads, on top of the nominal width. For an example, see: OGZ
edited Jan 14 at 20:08
Loong
266214
answered Jan 14 at 8:45
AEhereAEhere
1,455417
edited Jan 14 at 20:08
Loong
266214
edited Jan 14 at 20:08
Loong
266214
edited Jan 14 at 20:08
Loong
266214
266214
answered Jan 14 at 8:45
AEhereAEhere
1,455417
answered Jan 14 at 8:45
AEhereAEhere
1,455417
answered Jan 14 at 8:45
AEhereAEhere
1,455417
1,455417
add a comment |
add a comment |
$begingroup$
Because planes that landed towards the edge of the touch-down zone would run off the side of the runway when it narrowed.
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
$endgroup$
1
$begingroup$
That's (one of the reasons) why we have rudders and tillers - so that planes touching down off-center can be steered back to the centerline.
$endgroup$
– Sean
Jan 15 at 4:04
$begingroup$
@Sean and those aren't too effective until speed drops significantly for ground handling.
$endgroup$
– jwenting
Jan 15 at 6:28
14
$begingroup$
@Sean To provide enough time to slow so you can steer back safely, you'd probably need half the runway to be full-width and the second half could be tapered off. But that second half is the first half of the opposite-direction runway, so it has to be full-width too.
$endgroup$
– Dan Hulme
Jan 15 at 9:44
add a comment |
$begingroup$
Because planes that landed towards the edge of the touch-down zone would run off the side of the runway when it narrowed.
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
$endgroup$
1
$begingroup$
That's (one of the reasons) why we have rudders and tillers - so that planes touching down off-center can be steered back to the centerline.
$endgroup$
– Sean
Jan 15 at 4:04
$begingroup$
@Sean and those aren't too effective until speed drops significantly for ground handling.
$endgroup$
– jwenting
Jan 15 at 6:28
14
$begingroup$
@Sean To provide enough time to slow so you can steer back safely, you'd probably need half the runway to be full-width and the second half could be tapered off. But that second half is the first half of the opposite-direction runway, so it has to be full-width too.
$endgroup$
– Dan Hulme
Jan 15 at 9:44
add a comment |
$begingroup$
Because planes that landed towards the edge of the touch-down zone would run off the side of the runway when it narrowed.
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
$endgroup$
Because planes that landed towards the edge of the touch-down zone would run off the side of the runway when it narrowed.
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
answered Jan 14 at 23:43
David RicherbyDavid Richerby
9,78833478
9,78833478
1
$begingroup$
That's (one of the reasons) why we have rudders and tillers - so that planes touching down off-center can be steered back to the centerline.
$endgroup$
– Sean
Jan 15 at 4:04
$begingroup$
@Sean and those aren't too effective until speed drops significantly for ground handling.
$endgroup$
– jwenting
Jan 15 at 6:28
14
$begingroup$
@Sean To provide enough time to slow so you can steer back safely, you'd probably need half the runway to be full-width and the second half could be tapered off. But that second half is the first half of the opposite-direction runway, so it has to be full-width too.
$endgroup$
– Dan Hulme
Jan 15 at 9:44
add a comment |
1
$begingroup$
That's (one of the reasons) why we have rudders and tillers - so that planes touching down off-center can be steered back to the centerline.
$endgroup$
– Sean
Jan 15 at 4:04
$begingroup$
@Sean and those aren't too effective until speed drops significantly for ground handling.
$endgroup$
– jwenting
Jan 15 at 6:28
14
$begingroup$
@Sean To provide enough time to slow so you can steer back safely, you'd probably need half the runway to be full-width and the second half could be tapered off. But that second half is the first half of the opposite-direction runway, so it has to be full-width too.
$endgroup$
– Dan Hulme
Jan 15 at 9:44
1
1
$begingroup$
That's (one of the reasons) why we have rudders and tillers - so that planes touching down off-center can be steered back to the centerline.
$endgroup$
– Sean
Jan 15 at 4:04
$begingroup$
That's (one of the reasons) why we have rudders and tillers - so that planes touching down off-center can be steered back to the centerline.
$endgroup$
– Sean
Jan 15 at 4:04
$begingroup$
@Sean and those aren't too effective until speed drops significantly for ground handling.
$endgroup$
– jwenting
Jan 15 at 6:28
$begingroup$
@Sean and those aren't too effective until speed drops significantly for ground handling.
$endgroup$
– jwenting
Jan 15 at 6:28
14
14
$begingroup$
@Sean To provide enough time to slow so you can steer back safely, you'd probably need half the runway to be full-width and the second half could be tapered off. But that second half is the first half of the opposite-direction runway, so it has to be full-width too.
$endgroup$
– Dan Hulme
Jan 15 at 9:44
$begingroup$
@Sean To provide enough time to slow so you can steer back safely, you'd probably need half the runway to be full-width and the second half could be tapered off. But that second half is the first half of the opposite-direction runway, so it has to be full-width too.
$endgroup$
– Dan Hulme
Jan 15 at 9:44
add a comment |
$begingroup$
At least a few runways are divided by length. For example, once at Boeing Field (BFI) four general aviation light aircraft were cleared to land approximately at once on two runways. My VFR landing clearance was to land in the first half of runway 14R while another aircraft above and slightly ahead of me had to stay at 500 AGL(? I forget the exact number) until the threshold and then land on the second half. The left runway had something similar occurring at about the same time.
Having irregular width runways doesn't help this much. Also it is difficult to imagine that the non-ends would be graded any differently. In the overall project of constructing a runway, it is highly likely that the land preparation, utilities, and grading are like 80% of the cost of the surface. A forum exchange breakdown of a Canadian 7000 x 100 foot runway is:
$ 250,000 geotechnical analysis
$ 4,000,000 gravel (60 cm of 7.5 cm minus, 25 cm 1 cm minus)
$ 2,500,000 labor and equipment rental
$ 100,000 quality testing (compaction, etc.)
$ 2,000,000 asphalt (15 cm)
$ 200,000 lighting
$ 10,000 painted markings
----------
$ 9,060,000 total
Would making the shape narrower increase any of those costs? Probably. Certainly less materials should decrease the overall cost, and maybe labor could be economized.
For strong crosswind landings, I usually use all of whatever width there is!
answered Jan 15 at 0:25
wallykwallyk
23915
$endgroup$
2
$begingroup$
Interesting mixture of units. Runway area in feet and depth in centimetres :-)
$endgroup$
– uɐɪ
Jan 15 at 11:33
1
$begingroup$
@uɐɪ So volume is in square feet centimetres!
$endgroup$
– Oscar Bravo
Jan 15 at 14:12
1
$begingroup$
Similar thing happens at Oshkosh every year, right?
$endgroup$
– yshavit
Jan 15 at 16:06
add a comment |
$begingroup$
At least a few runways are divided by length. For example, once at Boeing Field (BFI) four general aviation light aircraft were cleared to land approximately at once on two runways. My VFR landing clearance was to land in the first half of runway 14R while another aircraft above and slightly ahead of me had to stay at 500 AGL(? I forget the exact number) until the threshold and then land on the second half. The left runway had something similar occurring at about the same time.
Having irregular width runways doesn't help this much. Also it is difficult to imagine that the non-ends would be graded any differently. In the overall project of constructing a runway, it is highly likely that the land preparation, utilities, and grading are like 80% of the cost of the surface. A forum exchange breakdown of a Canadian 7000 x 100 foot runway is:
$ 250,000 geotechnical analysis
$ 4,000,000 gravel (60 cm of 7.5 cm minus, 25 cm 1 cm minus)
$ 2,500,000 labor and equipment rental
$ 100,000 quality testing (compaction, etc.)
$ 2,000,000 asphalt (15 cm)
$ 200,000 lighting
$ 10,000 painted markings
----------
$ 9,060,000 total
Would making the shape narrower increase any of those costs? Probably. Certainly less materials should decrease the overall cost, and maybe labor could be economized.
For strong crosswind landings, I usually use all of whatever width there is!
answered Jan 15 at 0:25
wallykwallyk
23915
$endgroup$
2
$begingroup$
Interesting mixture of units. Runway area in feet and depth in centimetres :-)
$endgroup$
– uɐɪ
Jan 15 at 11:33
1
$begingroup$
@uɐɪ So volume is in square feet centimetres!
$endgroup$
– Oscar Bravo
Jan 15 at 14:12
1
$begingroup$
Similar thing happens at Oshkosh every year, right?
$endgroup$
– yshavit
Jan 15 at 16:06
add a comment |
$begingroup$
At least a few runways are divided by length. For example, once at Boeing Field (BFI) four general aviation light aircraft were cleared to land approximately at once on two runways. My VFR landing clearance was to land in the first half of runway 14R while another aircraft above and slightly ahead of me had to stay at 500 AGL(? I forget the exact number) until the threshold and then land on the second half. The left runway had something similar occurring at about the same time.
Having irregular width runways doesn't help this much. Also it is difficult to imagine that the non-ends would be graded any differently. In the overall project of constructing a runway, it is highly likely that the land preparation, utilities, and grading are like 80% of the cost of the surface. A forum exchange breakdown of a Canadian 7000 x 100 foot runway is:
$ 250,000 geotechnical analysis
$ 4,000,000 gravel (60 cm of 7.5 cm minus, 25 cm 1 cm minus)
$ 2,500,000 labor and equipment rental
$ 100,000 quality testing (compaction, etc.)
$ 2,000,000 asphalt (15 cm)
$ 200,000 lighting
$ 10,000 painted markings
----------
$ 9,060,000 total
Would making the shape narrower increase any of those costs? Probably. Certainly less materials should decrease the overall cost, and maybe labor could be economized.
For strong crosswind landings, I usually use all of whatever width there is!
answered Jan 15 at 0:25
wallykwallyk
23915
$endgroup$
At least a few runways are divided by length. For example, once at Boeing Field (BFI) four general aviation light aircraft were cleared to land approximately at once on two runways. My VFR landing clearance was to land in the first half of runway 14R while another aircraft above and slightly ahead of me had to stay at 500 AGL(? I forget the exact number) until the threshold and then land on the second half. The left runway had something similar occurring at about the same time.
Having irregular width runways doesn't help this much. Also it is difficult to imagine that the non-ends would be graded any differently. In the overall project of constructing a runway, it is highly likely that the land preparation, utilities, and grading are like 80% of the cost of the surface. A forum exchange breakdown of a Canadian 7000 x 100 foot runway is:
$ 250,000 geotechnical analysis
$ 4,000,000 gravel (60 cm of 7.5 cm minus, 25 cm 1 cm minus)
$ 2,500,000 labor and equipment rental
$ 100,000 quality testing (compaction, etc.)
$ 2,000,000 asphalt (15 cm)
$ 200,000 lighting
$ 10,000 painted markings
----------
$ 9,060,000 total
Would making the shape narrower increase any of those costs? Probably. Certainly less materials should decrease the overall cost, and maybe labor could be economized.
For strong crosswind landings, I usually use all of whatever width there is!
answered Jan 15 at 0:25
wallykwallyk
23915
answered Jan 15 at 0:25
wallykwallyk
23915
answered Jan 15 at 0:25
wallykwallyk
23915
answered Jan 15 at 0:25
wallykwallyk
23915
23915
2
$begingroup$
Interesting mixture of units. Runway area in feet and depth in centimetres :-)
$endgroup$
– uɐɪ
Jan 15 at 11:33
1
$begingroup$
@uɐɪ So volume is in square feet centimetres!
$endgroup$
– Oscar Bravo
Jan 15 at 14:12
1
$begingroup$
Similar thing happens at Oshkosh every year, right?
$endgroup$
– yshavit
Jan 15 at 16:06
add a comment |
2
$begingroup$
Interesting mixture of units. Runway area in feet and depth in centimetres :-)
$endgroup$
– uɐɪ
Jan 15 at 11:33
1
$begingroup$
@uɐɪ So volume is in square feet centimetres!
$endgroup$
– Oscar Bravo
Jan 15 at 14:12
1
$begingroup$
Similar thing happens at Oshkosh every year, right?
$endgroup$
– yshavit
Jan 15 at 16:06
2
2
$begingroup$
Interesting mixture of units. Runway area in feet and depth in centimetres :-)
$endgroup$
– uɐɪ
Jan 15 at 11:33
$begingroup$
Interesting mixture of units. Runway area in feet and depth in centimetres :-)
$endgroup$
– uɐɪ
Jan 15 at 11:33
1
1
$begingroup$
@uɐɪ So volume is in square feet centimetres!
$endgroup$
– Oscar Bravo
Jan 15 at 14:12
$begingroup$
@uɐɪ So volume is in square feet centimetres!
$endgroup$
– Oscar Bravo
Jan 15 at 14:12
1
1
$begingroup$
Similar thing happens at Oshkosh every year, right?
$endgroup$
– yshavit
Jan 15 at 16:06
$begingroup$
Similar thing happens at Oshkosh every year, right?
$endgroup$
– yshavit
Jan 15 at 16:06
add a comment |
Thanks for contributing an answer to Aviation Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faviation.stackexchange.com%2fquestions%2f59049%2fwhy-not-make-the-touchdown-zone-of-runways-wider-than-the-rest%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
wF,OZyl9rpU9h4NPfUkktnQdZzgl36,uUQ
18
$begingroup$
It sounds like the underlying assumption is that it is easier to stay centered after touchdown. I think that might not be true, crosswind and e.g. uneven braking power can be problematic even after the wheels are already on the ground.
$endgroup$
– jpa
Jan 14 at 10:26
7
$begingroup$
Consider the same question phrased a different way could we make some parts of the runway narrower than the rest?, and you'll probably come up with quite a few counter-arguments.
$endgroup$
– Toby Speight
Jan 14 at 13:19
13
$begingroup$
How would it give you a larger margin of error? It's no use having a wide touchdown zone if you're then going to go off the runway as it narrows.
$endgroup$
– Dan Hulme
Jan 14 at 17:22
2
$begingroup$
@dtgq What problem are you trying to solve? Planes running off runways is pretty rare.
$endgroup$
– zeta-band
Jan 15 at 0:15
1
$begingroup$
"if you touch down off the side of the runway" then you've screwed up badly and should have gone around.
$endgroup$
– Roger Lipscombe
Jan 15 at 11:49