Why is autolanding ILS a thing, but not autotakeoffing ITS?
$begingroup$
In this answer to the question of why zero-visibility landings are legal and routine but not zero-visibility takeoffs, the poster makes the following point:
When an aircraft lands in near zero visibility, it is a fully automated process that is actually done without input from the pilot. The pilots are only needed to taxi off the runway and park the aircraft. It is called "Autoland" and many of today's aircraft have it.
As of today no manufacturer has designed an aircraft with "Auto Takeoff" but I suppose it is not impossible.
(Emphasis added.)
Which seems odd, given that autolanding with an ILS is a mature technique using mature technology, and autotakeoffing with an ITS (instrument takeoff system) wouldn’t need much more on top of that (just some additional antennae on the aircraft’s tail and a couple new routines for the autopilot) - it’d mostly be pretty much an ILS running in reverse, something like this:
What’s the dealbreaker for an autotakeoff-supporting instrument takeoff system?
takeoff autopilot instrument-procedures visibility
$endgroup$
add a comment |
$begingroup$
In this answer to the question of why zero-visibility landings are legal and routine but not zero-visibility takeoffs, the poster makes the following point:
When an aircraft lands in near zero visibility, it is a fully automated process that is actually done without input from the pilot. The pilots are only needed to taxi off the runway and park the aircraft. It is called "Autoland" and many of today's aircraft have it.
As of today no manufacturer has designed an aircraft with "Auto Takeoff" but I suppose it is not impossible.
(Emphasis added.)
Which seems odd, given that autolanding with an ILS is a mature technique using mature technology, and autotakeoffing with an ITS (instrument takeoff system) wouldn’t need much more on top of that (just some additional antennae on the aircraft’s tail and a couple new routines for the autopilot) - it’d mostly be pretty much an ILS running in reverse, something like this:
What’s the dealbreaker for an autotakeoff-supporting instrument takeoff system?
takeoff autopilot instrument-procedures visibility
$endgroup$
1
$begingroup$
A failure, like a tire blowing or engine fire requires pilot intervention immediately. It would be better if the pilot as at the controls when it happened rather than having to disengage the automatic systems and play "catch up" with flying the plane. I'm sure this will get there at some point, but right now it's just better to have your hands on the controls and mind in the game during this critical phase.
$endgroup$
– Ron Beyer
2 hours ago
$begingroup$
@RonBeyer: Couldn't an autopilot be programmed to react to a failure like an flaming engine or exploding tyre, and do so more quickly than a human pilot could ever hope to do (like how we already have autospeedbrakedeployment for rejected takeoffs)?
$endgroup$
– Sean
2 hours ago
$begingroup$
Possible duplicate of Could aircraft already do a safe auto-takeoff with todays equipment?
$endgroup$
– Pondlife
1 hour ago
add a comment |
$begingroup$
In this answer to the question of why zero-visibility landings are legal and routine but not zero-visibility takeoffs, the poster makes the following point:
When an aircraft lands in near zero visibility, it is a fully automated process that is actually done without input from the pilot. The pilots are only needed to taxi off the runway and park the aircraft. It is called "Autoland" and many of today's aircraft have it.
As of today no manufacturer has designed an aircraft with "Auto Takeoff" but I suppose it is not impossible.
(Emphasis added.)
Which seems odd, given that autolanding with an ILS is a mature technique using mature technology, and autotakeoffing with an ITS (instrument takeoff system) wouldn’t need much more on top of that (just some additional antennae on the aircraft’s tail and a couple new routines for the autopilot) - it’d mostly be pretty much an ILS running in reverse, something like this:
What’s the dealbreaker for an autotakeoff-supporting instrument takeoff system?
takeoff autopilot instrument-procedures visibility
$endgroup$
In this answer to the question of why zero-visibility landings are legal and routine but not zero-visibility takeoffs, the poster makes the following point:
When an aircraft lands in near zero visibility, it is a fully automated process that is actually done without input from the pilot. The pilots are only needed to taxi off the runway and park the aircraft. It is called "Autoland" and many of today's aircraft have it.
As of today no manufacturer has designed an aircraft with "Auto Takeoff" but I suppose it is not impossible.
(Emphasis added.)
Which seems odd, given that autolanding with an ILS is a mature technique using mature technology, and autotakeoffing with an ITS (instrument takeoff system) wouldn’t need much more on top of that (just some additional antennae on the aircraft’s tail and a couple new routines for the autopilot) - it’d mostly be pretty much an ILS running in reverse, something like this:
What’s the dealbreaker for an autotakeoff-supporting instrument takeoff system?
takeoff autopilot instrument-procedures visibility
takeoff autopilot instrument-procedures visibility
asked 3 hours ago
SeanSean
4,68322459
4,68322459
1
$begingroup$
A failure, like a tire blowing or engine fire requires pilot intervention immediately. It would be better if the pilot as at the controls when it happened rather than having to disengage the automatic systems and play "catch up" with flying the plane. I'm sure this will get there at some point, but right now it's just better to have your hands on the controls and mind in the game during this critical phase.
$endgroup$
– Ron Beyer
2 hours ago
$begingroup$
@RonBeyer: Couldn't an autopilot be programmed to react to a failure like an flaming engine or exploding tyre, and do so more quickly than a human pilot could ever hope to do (like how we already have autospeedbrakedeployment for rejected takeoffs)?
$endgroup$
– Sean
2 hours ago
$begingroup$
Possible duplicate of Could aircraft already do a safe auto-takeoff with todays equipment?
$endgroup$
– Pondlife
1 hour ago
add a comment |
1
$begingroup$
A failure, like a tire blowing or engine fire requires pilot intervention immediately. It would be better if the pilot as at the controls when it happened rather than having to disengage the automatic systems and play "catch up" with flying the plane. I'm sure this will get there at some point, but right now it's just better to have your hands on the controls and mind in the game during this critical phase.
$endgroup$
– Ron Beyer
2 hours ago
$begingroup$
@RonBeyer: Couldn't an autopilot be programmed to react to a failure like an flaming engine or exploding tyre, and do so more quickly than a human pilot could ever hope to do (like how we already have autospeedbrakedeployment for rejected takeoffs)?
$endgroup$
– Sean
2 hours ago
$begingroup$
Possible duplicate of Could aircraft already do a safe auto-takeoff with todays equipment?
$endgroup$
– Pondlife
1 hour ago
1
1
$begingroup$
A failure, like a tire blowing or engine fire requires pilot intervention immediately. It would be better if the pilot as at the controls when it happened rather than having to disengage the automatic systems and play "catch up" with flying the plane. I'm sure this will get there at some point, but right now it's just better to have your hands on the controls and mind in the game during this critical phase.
$endgroup$
– Ron Beyer
2 hours ago
$begingroup$
A failure, like a tire blowing or engine fire requires pilot intervention immediately. It would be better if the pilot as at the controls when it happened rather than having to disengage the automatic systems and play "catch up" with flying the plane. I'm sure this will get there at some point, but right now it's just better to have your hands on the controls and mind in the game during this critical phase.
$endgroup$
– Ron Beyer
2 hours ago
$begingroup$
@RonBeyer: Couldn't an autopilot be programmed to react to a failure like an flaming engine or exploding tyre, and do so more quickly than a human pilot could ever hope to do (like how we already have autospeedbrakedeployment for rejected takeoffs)?
$endgroup$
– Sean
2 hours ago
$begingroup$
@RonBeyer: Couldn't an autopilot be programmed to react to a failure like an flaming engine or exploding tyre, and do so more quickly than a human pilot could ever hope to do (like how we already have autospeedbrakedeployment for rejected takeoffs)?
$endgroup$
– Sean
2 hours ago
$begingroup$
Possible duplicate of Could aircraft already do a safe auto-takeoff with todays equipment?
$endgroup$
– Pondlife
1 hour ago
$begingroup$
Possible duplicate of Could aircraft already do a safe auto-takeoff with todays equipment?
$endgroup$
– Pondlife
1 hour ago
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
You don't need the radar altimeter / reverse glide slope system, at all. The energy management required and the trimming are not easy and are in fact unsafe (you need to keep climbing at the best climb rate, in case of say birds). All you need is lateral guidance. Once you are wheels off, you are wheels off, continue the climb via the SID, for example, and be on your way (IFR flying).
Auto land category III B requires a minimum RVR (runway visual range) of 50/75-200 m (depending on the jurisdiction).
What if I told you LVTO (low visibility take-off) is a thing, and can go as low as 75 m RVR – as good as many CAT III B installations.
Here's a nice table from ICAO's Doc 9365 (Manual of All-Weather Operations):
Same as auto land, if you (the carrier and crew) and the plane are certified and current, and the right airport equipment (e.g., RVR transmissometers, runway lights, etc.) and procedures exist, you're good to go – only difference is that it'll be manual flying.
For the lateral guidance, localizers (or GLS) are in fact used for LVTO. (See: How does a HUD track a runway?)
$endgroup$
$begingroup$
The RVR/VIS numbers are a bit surprising. Usually the RVR and visibility are equal (300m ≅ 1,000ft, 150m ≅ 500ft) or almost so (500m ≅ 1,640ft, 400m ≅ 1300ft, 200m ≅ 660ft, 125m ≅ 410ft) with the visibility even rounded down, but for the lowest case the visibility is more as 300ft ≅ 90m.
$endgroup$
– Jan Hudec
1 hour ago
$begingroup$
Good observation @JanHudec - see here: aviation.stackexchange.com/q/30476/14897
$endgroup$
– ymb1
1 hour ago
add a comment |
$begingroup$
Autoland exists at least in part because a pilot can't safely hit (the right part of) the runway (at the right speed and attitude) without visual references, so a lot of precision electronic guidance equipment is needed, and then even more equipment to ensure the first equipment is working correctly.
In contrast, the sky is much bigger than the runway. It's comparatively easy for the pilot to hit the sky even without visual references (provided vis is good enough to taxi out). So none of that fancy stuff is necessary.
$endgroup$
$begingroup$
the sky is much bigger than the runway [citation needed]
$endgroup$
– Sanchises
1 min ago
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
You don't need the radar altimeter / reverse glide slope system, at all. The energy management required and the trimming are not easy and are in fact unsafe (you need to keep climbing at the best climb rate, in case of say birds). All you need is lateral guidance. Once you are wheels off, you are wheels off, continue the climb via the SID, for example, and be on your way (IFR flying).
Auto land category III B requires a minimum RVR (runway visual range) of 50/75-200 m (depending on the jurisdiction).
What if I told you LVTO (low visibility take-off) is a thing, and can go as low as 75 m RVR – as good as many CAT III B installations.
Here's a nice table from ICAO's Doc 9365 (Manual of All-Weather Operations):
Same as auto land, if you (the carrier and crew) and the plane are certified and current, and the right airport equipment (e.g., RVR transmissometers, runway lights, etc.) and procedures exist, you're good to go – only difference is that it'll be manual flying.
For the lateral guidance, localizers (or GLS) are in fact used for LVTO. (See: How does a HUD track a runway?)
$endgroup$
$begingroup$
The RVR/VIS numbers are a bit surprising. Usually the RVR and visibility are equal (300m ≅ 1,000ft, 150m ≅ 500ft) or almost so (500m ≅ 1,640ft, 400m ≅ 1300ft, 200m ≅ 660ft, 125m ≅ 410ft) with the visibility even rounded down, but for the lowest case the visibility is more as 300ft ≅ 90m.
$endgroup$
– Jan Hudec
1 hour ago
$begingroup$
Good observation @JanHudec - see here: aviation.stackexchange.com/q/30476/14897
$endgroup$
– ymb1
1 hour ago
add a comment |
$begingroup$
You don't need the radar altimeter / reverse glide slope system, at all. The energy management required and the trimming are not easy and are in fact unsafe (you need to keep climbing at the best climb rate, in case of say birds). All you need is lateral guidance. Once you are wheels off, you are wheels off, continue the climb via the SID, for example, and be on your way (IFR flying).
Auto land category III B requires a minimum RVR (runway visual range) of 50/75-200 m (depending on the jurisdiction).
What if I told you LVTO (low visibility take-off) is a thing, and can go as low as 75 m RVR – as good as many CAT III B installations.
Here's a nice table from ICAO's Doc 9365 (Manual of All-Weather Operations):
Same as auto land, if you (the carrier and crew) and the plane are certified and current, and the right airport equipment (e.g., RVR transmissometers, runway lights, etc.) and procedures exist, you're good to go – only difference is that it'll be manual flying.
For the lateral guidance, localizers (or GLS) are in fact used for LVTO. (See: How does a HUD track a runway?)
$endgroup$
$begingroup$
The RVR/VIS numbers are a bit surprising. Usually the RVR and visibility are equal (300m ≅ 1,000ft, 150m ≅ 500ft) or almost so (500m ≅ 1,640ft, 400m ≅ 1300ft, 200m ≅ 660ft, 125m ≅ 410ft) with the visibility even rounded down, but for the lowest case the visibility is more as 300ft ≅ 90m.
$endgroup$
– Jan Hudec
1 hour ago
$begingroup$
Good observation @JanHudec - see here: aviation.stackexchange.com/q/30476/14897
$endgroup$
– ymb1
1 hour ago
add a comment |
$begingroup$
You don't need the radar altimeter / reverse glide slope system, at all. The energy management required and the trimming are not easy and are in fact unsafe (you need to keep climbing at the best climb rate, in case of say birds). All you need is lateral guidance. Once you are wheels off, you are wheels off, continue the climb via the SID, for example, and be on your way (IFR flying).
Auto land category III B requires a minimum RVR (runway visual range) of 50/75-200 m (depending on the jurisdiction).
What if I told you LVTO (low visibility take-off) is a thing, and can go as low as 75 m RVR – as good as many CAT III B installations.
Here's a nice table from ICAO's Doc 9365 (Manual of All-Weather Operations):
Same as auto land, if you (the carrier and crew) and the plane are certified and current, and the right airport equipment (e.g., RVR transmissometers, runway lights, etc.) and procedures exist, you're good to go – only difference is that it'll be manual flying.
For the lateral guidance, localizers (or GLS) are in fact used for LVTO. (See: How does a HUD track a runway?)
$endgroup$
You don't need the radar altimeter / reverse glide slope system, at all. The energy management required and the trimming are not easy and are in fact unsafe (you need to keep climbing at the best climb rate, in case of say birds). All you need is lateral guidance. Once you are wheels off, you are wheels off, continue the climb via the SID, for example, and be on your way (IFR flying).
Auto land category III B requires a minimum RVR (runway visual range) of 50/75-200 m (depending on the jurisdiction).
What if I told you LVTO (low visibility take-off) is a thing, and can go as low as 75 m RVR – as good as many CAT III B installations.
Here's a nice table from ICAO's Doc 9365 (Manual of All-Weather Operations):
Same as auto land, if you (the carrier and crew) and the plane are certified and current, and the right airport equipment (e.g., RVR transmissometers, runway lights, etc.) and procedures exist, you're good to go – only difference is that it'll be manual flying.
For the lateral guidance, localizers (or GLS) are in fact used for LVTO. (See: How does a HUD track a runway?)
answered 2 hours ago
ymb1ymb1
65.6k6210348
65.6k6210348
$begingroup$
The RVR/VIS numbers are a bit surprising. Usually the RVR and visibility are equal (300m ≅ 1,000ft, 150m ≅ 500ft) or almost so (500m ≅ 1,640ft, 400m ≅ 1300ft, 200m ≅ 660ft, 125m ≅ 410ft) with the visibility even rounded down, but for the lowest case the visibility is more as 300ft ≅ 90m.
$endgroup$
– Jan Hudec
1 hour ago
$begingroup$
Good observation @JanHudec - see here: aviation.stackexchange.com/q/30476/14897
$endgroup$
– ymb1
1 hour ago
add a comment |
$begingroup$
The RVR/VIS numbers are a bit surprising. Usually the RVR and visibility are equal (300m ≅ 1,000ft, 150m ≅ 500ft) or almost so (500m ≅ 1,640ft, 400m ≅ 1300ft, 200m ≅ 660ft, 125m ≅ 410ft) with the visibility even rounded down, but for the lowest case the visibility is more as 300ft ≅ 90m.
$endgroup$
– Jan Hudec
1 hour ago
$begingroup$
Good observation @JanHudec - see here: aviation.stackexchange.com/q/30476/14897
$endgroup$
– ymb1
1 hour ago
$begingroup$
The RVR/VIS numbers are a bit surprising. Usually the RVR and visibility are equal (300m ≅ 1,000ft, 150m ≅ 500ft) or almost so (500m ≅ 1,640ft, 400m ≅ 1300ft, 200m ≅ 660ft, 125m ≅ 410ft) with the visibility even rounded down, but for the lowest case the visibility is more as 300ft ≅ 90m.
$endgroup$
– Jan Hudec
1 hour ago
$begingroup$
The RVR/VIS numbers are a bit surprising. Usually the RVR and visibility are equal (300m ≅ 1,000ft, 150m ≅ 500ft) or almost so (500m ≅ 1,640ft, 400m ≅ 1300ft, 200m ≅ 660ft, 125m ≅ 410ft) with the visibility even rounded down, but for the lowest case the visibility is more as 300ft ≅ 90m.
$endgroup$
– Jan Hudec
1 hour ago
$begingroup$
Good observation @JanHudec - see here: aviation.stackexchange.com/q/30476/14897
$endgroup$
– ymb1
1 hour ago
$begingroup$
Good observation @JanHudec - see here: aviation.stackexchange.com/q/30476/14897
$endgroup$
– ymb1
1 hour ago
add a comment |
$begingroup$
Autoland exists at least in part because a pilot can't safely hit (the right part of) the runway (at the right speed and attitude) without visual references, so a lot of precision electronic guidance equipment is needed, and then even more equipment to ensure the first equipment is working correctly.
In contrast, the sky is much bigger than the runway. It's comparatively easy for the pilot to hit the sky even without visual references (provided vis is good enough to taxi out). So none of that fancy stuff is necessary.
$endgroup$
$begingroup$
the sky is much bigger than the runway [citation needed]
$endgroup$
– Sanchises
1 min ago
add a comment |
$begingroup$
Autoland exists at least in part because a pilot can't safely hit (the right part of) the runway (at the right speed and attitude) without visual references, so a lot of precision electronic guidance equipment is needed, and then even more equipment to ensure the first equipment is working correctly.
In contrast, the sky is much bigger than the runway. It's comparatively easy for the pilot to hit the sky even without visual references (provided vis is good enough to taxi out). So none of that fancy stuff is necessary.
$endgroup$
$begingroup$
the sky is much bigger than the runway [citation needed]
$endgroup$
– Sanchises
1 min ago
add a comment |
$begingroup$
Autoland exists at least in part because a pilot can't safely hit (the right part of) the runway (at the right speed and attitude) without visual references, so a lot of precision electronic guidance equipment is needed, and then even more equipment to ensure the first equipment is working correctly.
In contrast, the sky is much bigger than the runway. It's comparatively easy for the pilot to hit the sky even without visual references (provided vis is good enough to taxi out). So none of that fancy stuff is necessary.
$endgroup$
Autoland exists at least in part because a pilot can't safely hit (the right part of) the runway (at the right speed and attitude) without visual references, so a lot of precision electronic guidance equipment is needed, and then even more equipment to ensure the first equipment is working correctly.
In contrast, the sky is much bigger than the runway. It's comparatively easy for the pilot to hit the sky even without visual references (provided vis is good enough to taxi out). So none of that fancy stuff is necessary.
answered 2 hours ago
pericynthionpericynthion
2,2411017
2,2411017
$begingroup$
the sky is much bigger than the runway [citation needed]
$endgroup$
– Sanchises
1 min ago
add a comment |
$begingroup$
the sky is much bigger than the runway [citation needed]
$endgroup$
– Sanchises
1 min ago
$begingroup$
the sky is much bigger than the runway [citation needed]
$endgroup$
– Sanchises
1 min ago
$begingroup$
the sky is much bigger than the runway [citation needed]
$endgroup$
– Sanchises
1 min ago
add a comment |
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$begingroup$
A failure, like a tire blowing or engine fire requires pilot intervention immediately. It would be better if the pilot as at the controls when it happened rather than having to disengage the automatic systems and play "catch up" with flying the plane. I'm sure this will get there at some point, but right now it's just better to have your hands on the controls and mind in the game during this critical phase.
$endgroup$
– Ron Beyer
2 hours ago
$begingroup$
@RonBeyer: Couldn't an autopilot be programmed to react to a failure like an flaming engine or exploding tyre, and do so more quickly than a human pilot could ever hope to do (like how we already have autospeedbrakedeployment for rejected takeoffs)?
$endgroup$
– Sean
2 hours ago
$begingroup$
Possible duplicate of Could aircraft already do a safe auto-takeoff with todays equipment?
$endgroup$
– Pondlife
1 hour ago