Why is indicated airspeed rather than ground speed used during the takeoff roll?What is the difference between ground speed and airspeed?Does adding flaps during ground roll perform better in short-field takeoff?What is the reference used when measuring flight speed?What's the difference between Rotation speed vs takeoff speed?What aircraft fly faster than 250 knots indicated airspeed under 10,000 feet for safety reasons?Why does indicated airspeed change with altitude?How to calculate normal takeoff ground roll when the POH only has Short Field Takeoff tables?In light aircraft, non-instrument flight, apply (nearly) full aft elevator before beginning the takeoff roll or at some predetermined speed?Why is the normal operating airspeed so much lower than the cruise speed in this table?Why do pilots normally fly by CAS rather than TAS?
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Why is indicated airspeed rather than ground speed used during the takeoff roll?
What is the difference between ground speed and airspeed?Does adding flaps during ground roll perform better in short-field takeoff?What is the reference used when measuring flight speed?What's the difference between Rotation speed vs takeoff speed?What aircraft fly faster than 250 knots indicated airspeed under 10,000 feet for safety reasons?Why does indicated airspeed change with altitude?How to calculate normal takeoff ground roll when the POH only has Short Field Takeoff tables?In light aircraft, non-instrument flight, apply (nearly) full aft elevator before beginning the takeoff roll or at some predetermined speed?Why is the normal operating airspeed so much lower than the cruise speed in this table?Why do pilots normally fly by CAS rather than TAS?
$begingroup$
My instructor asked me this question during my lesson and I couldn't come up with any answers. He asked why do I need to look at the indicated airspeed rather than ground speed when in takeoff roll or as soon as we touchdown? There is this procedure in my airline that we have to call out airspeeds when we are rolling for takeoff (ex: "80 kts" before THR HOLD).
It would be great if you could give me the reference to back it up.
takeoff airspeed
edited 12 hours ago
ymb1
67.3k7213357
asked 12 hours ago
SteveSteve
191
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
|
show 2 more comments
$begingroup$
My instructor asked me this question during my lesson and I couldn't come up with any answers. He asked why do I need to look at the indicated airspeed rather than ground speed when in takeoff roll or as soon as we touchdown? There is this procedure in my airline that we have to call out airspeeds when we are rolling for takeoff (ex: "80 kts" before THR HOLD).
It would be great if you could give me the reference to back it up.
takeoff airspeed
edited 12 hours ago
ymb1
67.3k7213357
asked 12 hours ago
SteveSteve
191
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
21
$begingroup$
It seems you are a commercial pilot working at an airline and being trained on a new aircraft type. If that is true, I find it hard to believe that you don't understand the difference between indicated airspeed and ground speed.
$endgroup$
– Mike Sowsun
9 hours ago
2
$begingroup$
What airplane are you flying that has a groundspeed indicator?
$endgroup$
– Wirewrap
7 hours ago
3
$begingroup$
@MikeSowsun Sad (and scary) but all too common (bell curve effect?) I once knew a commercial pilot who had to ask why potato chip bags burst when taking them up from Denver (elev ~5000 ft) to a ski resort at 11,000 feet in the Rockies.
$endgroup$
– Jim Garrison
6 hours ago
2
$begingroup$
@Wirewrap Every GPS I've seen displays current ground speed. In a glass cockpit, it's often put near IAS/TAS on the screen, unlike in a six-pack layout.
$endgroup$
– StephenS
6 hours ago
$begingroup$
@Wirewrap in a glass cockpit the GS will be with navigation data, not with primary flight display data like the speed tape, because ground speed is a navigation related data point, not a flying related data point.
$endgroup$
– John K
5 hours ago
|
show 2 more comments
$begingroup$
My instructor asked me this question during my lesson and I couldn't come up with any answers. He asked why do I need to look at the indicated airspeed rather than ground speed when in takeoff roll or as soon as we touchdown? There is this procedure in my airline that we have to call out airspeeds when we are rolling for takeoff (ex: "80 kts" before THR HOLD).
It would be great if you could give me the reference to back it up.
takeoff airspeed
edited 12 hours ago
ymb1
67.3k7213357
asked 12 hours ago
SteveSteve
191
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
My instructor asked me this question during my lesson and I couldn't come up with any answers. He asked why do I need to look at the indicated airspeed rather than ground speed when in takeoff roll or as soon as we touchdown? There is this procedure in my airline that we have to call out airspeeds when we are rolling for takeoff (ex: "80 kts" before THR HOLD).
It would be great if you could give me the reference to back it up.
takeoff airspeed
takeoff airspeed
edited 12 hours ago
ymb1
67.3k7213357
asked 12 hours ago
SteveSteve
191
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 12 hours ago
ymb1
67.3k7213357
asked 12 hours ago
SteveSteve
191
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 12 hours ago
ymb1
67.3k7213357
edited 12 hours ago
ymb1
67.3k7213357
edited 12 hours ago
ymb1
67.3k7213357
67.3k7213357
asked 12 hours ago
SteveSteve
191
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 12 hours ago
SteveSteve
191
asked 12 hours ago
SteveSteve
191
191
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
21
$begingroup$
It seems you are a commercial pilot working at an airline and being trained on a new aircraft type. If that is true, I find it hard to believe that you don't understand the difference between indicated airspeed and ground speed.
$endgroup$
– Mike Sowsun
9 hours ago
2
$begingroup$
What airplane are you flying that has a groundspeed indicator?
$endgroup$
– Wirewrap
7 hours ago
3
$begingroup$
@MikeSowsun Sad (and scary) but all too common (bell curve effect?) I once knew a commercial pilot who had to ask why potato chip bags burst when taking them up from Denver (elev ~5000 ft) to a ski resort at 11,000 feet in the Rockies.
$endgroup$
– Jim Garrison
6 hours ago
2
$begingroup$
@Wirewrap Every GPS I've seen displays current ground speed. In a glass cockpit, it's often put near IAS/TAS on the screen, unlike in a six-pack layout.
$endgroup$
– StephenS
6 hours ago
$begingroup$
@Wirewrap in a glass cockpit the GS will be with navigation data, not with primary flight display data like the speed tape, because ground speed is a navigation related data point, not a flying related data point.
$endgroup$
– John K
5 hours ago
|
show 2 more comments
21
$begingroup$
It seems you are a commercial pilot working at an airline and being trained on a new aircraft type. If that is true, I find it hard to believe that you don't understand the difference between indicated airspeed and ground speed.
$endgroup$
– Mike Sowsun
9 hours ago
2
$begingroup$
What airplane are you flying that has a groundspeed indicator?
$endgroup$
– Wirewrap
7 hours ago
3
$begingroup$
@MikeSowsun Sad (and scary) but all too common (bell curve effect?) I once knew a commercial pilot who had to ask why potato chip bags burst when taking them up from Denver (elev ~5000 ft) to a ski resort at 11,000 feet in the Rockies.
$endgroup$
– Jim Garrison
6 hours ago
2
$begingroup$
@Wirewrap Every GPS I've seen displays current ground speed. In a glass cockpit, it's often put near IAS/TAS on the screen, unlike in a six-pack layout.
$endgroup$
– StephenS
6 hours ago
$begingroup$
@Wirewrap in a glass cockpit the GS will be with navigation data, not with primary flight display data like the speed tape, because ground speed is a navigation related data point, not a flying related data point.
$endgroup$
– John K
5 hours ago
21
21
$begingroup$
It seems you are a commercial pilot working at an airline and being trained on a new aircraft type. If that is true, I find it hard to believe that you don't understand the difference between indicated airspeed and ground speed.
$endgroup$
– Mike Sowsun
9 hours ago
$begingroup$
It seems you are a commercial pilot working at an airline and being trained on a new aircraft type. If that is true, I find it hard to believe that you don't understand the difference between indicated airspeed and ground speed.
$endgroup$
– Mike Sowsun
9 hours ago
2
2
$begingroup$
What airplane are you flying that has a groundspeed indicator?
$endgroup$
– Wirewrap
7 hours ago
$begingroup$
What airplane are you flying that has a groundspeed indicator?
$endgroup$
– Wirewrap
7 hours ago
3
3
$begingroup$
@MikeSowsun Sad (and scary) but all too common (bell curve effect?) I once knew a commercial pilot who had to ask why potato chip bags burst when taking them up from Denver (elev ~5000 ft) to a ski resort at 11,000 feet in the Rockies.
$endgroup$
– Jim Garrison
6 hours ago
$begingroup$
@MikeSowsun Sad (and scary) but all too common (bell curve effect?) I once knew a commercial pilot who had to ask why potato chip bags burst when taking them up from Denver (elev ~5000 ft) to a ski resort at 11,000 feet in the Rockies.
$endgroup$
– Jim Garrison
6 hours ago
2
2
$begingroup$
@Wirewrap Every GPS I've seen displays current ground speed. In a glass cockpit, it's often put near IAS/TAS on the screen, unlike in a six-pack layout.
$endgroup$
– StephenS
6 hours ago
$begingroup$
@Wirewrap Every GPS I've seen displays current ground speed. In a glass cockpit, it's often put near IAS/TAS on the screen, unlike in a six-pack layout.
$endgroup$
– StephenS
6 hours ago
$begingroup$
@Wirewrap in a glass cockpit the GS will be with navigation data, not with primary flight display data like the speed tape, because ground speed is a navigation related data point, not a flying related data point.
$endgroup$
– John K
5 hours ago
$begingroup$
@Wirewrap in a glass cockpit the GS will be with navigation data, not with primary flight display data like the speed tape, because ground speed is a navigation related data point, not a flying related data point.
$endgroup$
– John K
5 hours ago
|
show 2 more comments
4 Answers
4
active
oldest
votes
$begingroup$
Because what determines the amount of lift generated is the indicated airspeed, not the ground speed. As usual, it is always easier to think about an extreme case. If you have an aircraft with VR (speed at rotation for takeoff) of 90 knots, and there is an 80 knots head wind, in theory it will rotate with ground speed of 10 knots even though the indicated airspeed will be 90 knots.
edited 6 hours ago
StephenS
4,1611725
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
$endgroup$
1
$begingroup$
Given this is a relatively simple question, probably best not to assume OP knows what Vr is.
$endgroup$
– Notts90
11 hours ago
6
$begingroup$
@Notts90 True, but it seems like OP is a pilot or studying to become one. Let's hope they know what Vr is
$endgroup$
– DeepSpace
11 hours ago
2
$begingroup$
My guess is airline-sponsored primary training. I'd hope he knows what Vr is by now, but I'm not sure we can assume it was explained correctly if he's asking this question.
$endgroup$
– StephenS
8 hours ago
2
$begingroup$
I don't remember offhand what every V speed means, and this site isn't exclusively for pilots anyway, so why not tell everyone what Vr is? Save some google searches.
$endgroup$
– Xen2050
7 hours ago
2
$begingroup$
For those interested: Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.
$endgroup$
– Mast
6 hours ago
|
show 3 more comments
$begingroup$
Because wings work on air moving past them, not ground moving below them.
Heck, in a 35 knot headwind, the Antonov-2 could be rolling backwards at 2 knots and still take off!
answered 6 hours ago
HarperHarper
3,381620
$endgroup$
$begingroup$
This is already explained in the existing answers. Why add one more?
$endgroup$
– Mast
6 hours ago
$begingroup$
@mast My explanation is far simpler. Which seems to be warranted here.
$endgroup$
– Harper
6 hours ago
add a comment |
$begingroup$
Airspeed is always important as it determines lift which keeps you in the air. At the moment of takeoff or landing, airspeed is critical because it is the point at which you transition to or from flight; you need to be going fast enough but not too fast so that the transition is positive without being abrupt or overly stressful on aircraft components.
Ground speed matters in navigation because it determines flight time which affects fuel required to get from A to B.
answered 5 hours ago
Anthony XAnthony X
1,8091116
$endgroup$
add a comment |
$begingroup$
The IAS includes factors such as Wind Component (Tail, Head or Cross), Pressure and Temperature. All these have an influence on your takeoff. The takeoff Speed Vr is calculated as Indicated Airspeed. Imagine you have a Headwind Component of +50. You Groundspeed would be way lower than your Airspeed. What counts is the amount of air that flows over the wing in order to takeoff, not the speed relative to the ground.
answered 11 hours ago
WindshearWindshear
1113
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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add a comment |
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4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Because what determines the amount of lift generated is the indicated airspeed, not the ground speed. As usual, it is always easier to think about an extreme case. If you have an aircraft with VR (speed at rotation for takeoff) of 90 knots, and there is an 80 knots head wind, in theory it will rotate with ground speed of 10 knots even though the indicated airspeed will be 90 knots.
edited 6 hours ago
StephenS
4,1611725
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
$endgroup$
1
$begingroup$
Given this is a relatively simple question, probably best not to assume OP knows what Vr is.
$endgroup$
– Notts90
11 hours ago
6
$begingroup$
@Notts90 True, but it seems like OP is a pilot or studying to become one. Let's hope they know what Vr is
$endgroup$
– DeepSpace
11 hours ago
2
$begingroup$
My guess is airline-sponsored primary training. I'd hope he knows what Vr is by now, but I'm not sure we can assume it was explained correctly if he's asking this question.
$endgroup$
– StephenS
8 hours ago
2
$begingroup$
I don't remember offhand what every V speed means, and this site isn't exclusively for pilots anyway, so why not tell everyone what Vr is? Save some google searches.
$endgroup$
– Xen2050
7 hours ago
2
$begingroup$
For those interested: Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.
$endgroup$
– Mast
6 hours ago
|
show 3 more comments
$begingroup$
Because what determines the amount of lift generated is the indicated airspeed, not the ground speed. As usual, it is always easier to think about an extreme case. If you have an aircraft with VR (speed at rotation for takeoff) of 90 knots, and there is an 80 knots head wind, in theory it will rotate with ground speed of 10 knots even though the indicated airspeed will be 90 knots.
edited 6 hours ago
StephenS
4,1611725
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
$endgroup$
1
$begingroup$
Given this is a relatively simple question, probably best not to assume OP knows what Vr is.
$endgroup$
– Notts90
11 hours ago
6
$begingroup$
@Notts90 True, but it seems like OP is a pilot or studying to become one. Let's hope they know what Vr is
$endgroup$
– DeepSpace
11 hours ago
2
$begingroup$
My guess is airline-sponsored primary training. I'd hope he knows what Vr is by now, but I'm not sure we can assume it was explained correctly if he's asking this question.
$endgroup$
– StephenS
8 hours ago
2
$begingroup$
I don't remember offhand what every V speed means, and this site isn't exclusively for pilots anyway, so why not tell everyone what Vr is? Save some google searches.
$endgroup$
– Xen2050
7 hours ago
2
$begingroup$
For those interested: Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.
$endgroup$
– Mast
6 hours ago
|
show 3 more comments
$begingroup$
Because what determines the amount of lift generated is the indicated airspeed, not the ground speed. As usual, it is always easier to think about an extreme case. If you have an aircraft with VR (speed at rotation for takeoff) of 90 knots, and there is an 80 knots head wind, in theory it will rotate with ground speed of 10 knots even though the indicated airspeed will be 90 knots.
edited 6 hours ago
StephenS
4,1611725
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
$endgroup$
Because what determines the amount of lift generated is the indicated airspeed, not the ground speed. As usual, it is always easier to think about an extreme case. If you have an aircraft with VR (speed at rotation for takeoff) of 90 knots, and there is an 80 knots head wind, in theory it will rotate with ground speed of 10 knots even though the indicated airspeed will be 90 knots.
edited 6 hours ago
StephenS
4,1611725
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
edited 6 hours ago
StephenS
4,1611725
edited 6 hours ago
StephenS
4,1611725
edited 6 hours ago
StephenS
4,1611725
4,1611725
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
answered 12 hours ago
DeepSpaceDeepSpace
1,435613
1,435613
1
$begingroup$
Given this is a relatively simple question, probably best not to assume OP knows what Vr is.
$endgroup$
– Notts90
11 hours ago
6
$begingroup$
@Notts90 True, but it seems like OP is a pilot or studying to become one. Let's hope they know what Vr is
$endgroup$
– DeepSpace
11 hours ago
2
$begingroup$
My guess is airline-sponsored primary training. I'd hope he knows what Vr is by now, but I'm not sure we can assume it was explained correctly if he's asking this question.
$endgroup$
– StephenS
8 hours ago
2
$begingroup$
I don't remember offhand what every V speed means, and this site isn't exclusively for pilots anyway, so why not tell everyone what Vr is? Save some google searches.
$endgroup$
– Xen2050
7 hours ago
2
$begingroup$
For those interested: Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.
$endgroup$
– Mast
6 hours ago
|
show 3 more comments
1
$begingroup$
Given this is a relatively simple question, probably best not to assume OP knows what Vr is.
$endgroup$
– Notts90
11 hours ago
6
$begingroup$
@Notts90 True, but it seems like OP is a pilot or studying to become one. Let's hope they know what Vr is
$endgroup$
– DeepSpace
11 hours ago
2
$begingroup$
My guess is airline-sponsored primary training. I'd hope he knows what Vr is by now, but I'm not sure we can assume it was explained correctly if he's asking this question.
$endgroup$
– StephenS
8 hours ago
2
$begingroup$
I don't remember offhand what every V speed means, and this site isn't exclusively for pilots anyway, so why not tell everyone what Vr is? Save some google searches.
$endgroup$
– Xen2050
7 hours ago
2
$begingroup$
For those interested: Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.
$endgroup$
– Mast
6 hours ago
1
1
$begingroup$
Given this is a relatively simple question, probably best not to assume OP knows what Vr is.
$endgroup$
– Notts90
11 hours ago
$begingroup$
Given this is a relatively simple question, probably best not to assume OP knows what Vr is.
$endgroup$
– Notts90
11 hours ago
6
6
$begingroup$
@Notts90 True, but it seems like OP is a pilot or studying to become one. Let's hope they know what Vr is
$endgroup$
– DeepSpace
11 hours ago
$begingroup$
@Notts90 True, but it seems like OP is a pilot or studying to become one. Let's hope they know what Vr is
$endgroup$
– DeepSpace
11 hours ago
2
2
$begingroup$
My guess is airline-sponsored primary training. I'd hope he knows what Vr is by now, but I'm not sure we can assume it was explained correctly if he's asking this question.
$endgroup$
– StephenS
8 hours ago
$begingroup$
My guess is airline-sponsored primary training. I'd hope he knows what Vr is by now, but I'm not sure we can assume it was explained correctly if he's asking this question.
$endgroup$
– StephenS
8 hours ago
2
2
$begingroup$
I don't remember offhand what every V speed means, and this site isn't exclusively for pilots anyway, so why not tell everyone what Vr is? Save some google searches.
$endgroup$
– Xen2050
7 hours ago
$begingroup$
I don't remember offhand what every V speed means, and this site isn't exclusively for pilots anyway, so why not tell everyone what Vr is? Save some google searches.
$endgroup$
– Xen2050
7 hours ago
2
2
$begingroup$
For those interested: Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.
$endgroup$
– Mast
6 hours ago
$begingroup$
For those interested: Vr is defined as the speed at which the rotation of the aircraft should be initiated to takeoff attitude.
$endgroup$
– Mast
6 hours ago
|
show 3 more comments
$begingroup$
Because wings work on air moving past them, not ground moving below them.
Heck, in a 35 knot headwind, the Antonov-2 could be rolling backwards at 2 knots and still take off!
answered 6 hours ago
HarperHarper
3,381620
$endgroup$
$begingroup$
This is already explained in the existing answers. Why add one more?
$endgroup$
– Mast
6 hours ago
$begingroup$
@mast My explanation is far simpler. Which seems to be warranted here.
$endgroup$
– Harper
6 hours ago
add a comment |
$begingroup$
Because wings work on air moving past them, not ground moving below them.
Heck, in a 35 knot headwind, the Antonov-2 could be rolling backwards at 2 knots and still take off!
answered 6 hours ago
HarperHarper
3,381620
$endgroup$
$begingroup$
This is already explained in the existing answers. Why add one more?
$endgroup$
– Mast
6 hours ago
$begingroup$
@mast My explanation is far simpler. Which seems to be warranted here.
$endgroup$
– Harper
6 hours ago
add a comment |
$begingroup$
Because wings work on air moving past them, not ground moving below them.
Heck, in a 35 knot headwind, the Antonov-2 could be rolling backwards at 2 knots and still take off!
answered 6 hours ago
HarperHarper
3,381620
$endgroup$
Because wings work on air moving past them, not ground moving below them.
Heck, in a 35 knot headwind, the Antonov-2 could be rolling backwards at 2 knots and still take off!
answered 6 hours ago
HarperHarper
3,381620
edited 6 hours ago
answered 6 hours ago
HarperHarper
3,381620
answered 6 hours ago
HarperHarper
3,381620
answered 6 hours ago
HarperHarper
3,381620
3,381620
$begingroup$
This is already explained in the existing answers. Why add one more?
$endgroup$
– Mast
6 hours ago
$begingroup$
@mast My explanation is far simpler. Which seems to be warranted here.
$endgroup$
– Harper
6 hours ago
add a comment |
$begingroup$
This is already explained in the existing answers. Why add one more?
$endgroup$
– Mast
6 hours ago
$begingroup$
@mast My explanation is far simpler. Which seems to be warranted here.
$endgroup$
– Harper
6 hours ago
$begingroup$
This is already explained in the existing answers. Why add one more?
$endgroup$
– Mast
6 hours ago
$begingroup$
This is already explained in the existing answers. Why add one more?
$endgroup$
– Mast
6 hours ago
$begingroup$
@mast My explanation is far simpler. Which seems to be warranted here.
$endgroup$
– Harper
6 hours ago
$begingroup$
@mast My explanation is far simpler. Which seems to be warranted here.
$endgroup$
– Harper
6 hours ago
add a comment |
$begingroup$
Airspeed is always important as it determines lift which keeps you in the air. At the moment of takeoff or landing, airspeed is critical because it is the point at which you transition to or from flight; you need to be going fast enough but not too fast so that the transition is positive without being abrupt or overly stressful on aircraft components.
Ground speed matters in navigation because it determines flight time which affects fuel required to get from A to B.
answered 5 hours ago
Anthony XAnthony X
1,8091116
$endgroup$
add a comment |
$begingroup$
Airspeed is always important as it determines lift which keeps you in the air. At the moment of takeoff or landing, airspeed is critical because it is the point at which you transition to or from flight; you need to be going fast enough but not too fast so that the transition is positive without being abrupt or overly stressful on aircraft components.
Ground speed matters in navigation because it determines flight time which affects fuel required to get from A to B.
answered 5 hours ago
Anthony XAnthony X
1,8091116
$endgroup$
add a comment |
$begingroup$
Airspeed is always important as it determines lift which keeps you in the air. At the moment of takeoff or landing, airspeed is critical because it is the point at which you transition to or from flight; you need to be going fast enough but not too fast so that the transition is positive without being abrupt or overly stressful on aircraft components.
Ground speed matters in navigation because it determines flight time which affects fuel required to get from A to B.
answered 5 hours ago
Anthony XAnthony X
1,8091116
$endgroup$
Airspeed is always important as it determines lift which keeps you in the air. At the moment of takeoff or landing, airspeed is critical because it is the point at which you transition to or from flight; you need to be going fast enough but not too fast so that the transition is positive without being abrupt or overly stressful on aircraft components.
Ground speed matters in navigation because it determines flight time which affects fuel required to get from A to B.
answered 5 hours ago
Anthony XAnthony X
1,8091116
answered 5 hours ago
Anthony XAnthony X
1,8091116
answered 5 hours ago
Anthony XAnthony X
1,8091116
answered 5 hours ago
Anthony XAnthony X
1,8091116
1,8091116
add a comment |
add a comment |
$begingroup$
The IAS includes factors such as Wind Component (Tail, Head or Cross), Pressure and Temperature. All these have an influence on your takeoff. The takeoff Speed Vr is calculated as Indicated Airspeed. Imagine you have a Headwind Component of +50. You Groundspeed would be way lower than your Airspeed. What counts is the amount of air that flows over the wing in order to takeoff, not the speed relative to the ground.
answered 11 hours ago
WindshearWindshear
1113
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
add a comment |
$begingroup$
The IAS includes factors such as Wind Component (Tail, Head or Cross), Pressure and Temperature. All these have an influence on your takeoff. The takeoff Speed Vr is calculated as Indicated Airspeed. Imagine you have a Headwind Component of +50. You Groundspeed would be way lower than your Airspeed. What counts is the amount of air that flows over the wing in order to takeoff, not the speed relative to the ground.
answered 11 hours ago
WindshearWindshear
1113
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
add a comment |
$begingroup$
The IAS includes factors such as Wind Component (Tail, Head or Cross), Pressure and Temperature. All these have an influence on your takeoff. The takeoff Speed Vr is calculated as Indicated Airspeed. Imagine you have a Headwind Component of +50. You Groundspeed would be way lower than your Airspeed. What counts is the amount of air that flows over the wing in order to takeoff, not the speed relative to the ground.
answered 11 hours ago
WindshearWindshear
1113
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
The IAS includes factors such as Wind Component (Tail, Head or Cross), Pressure and Temperature. All these have an influence on your takeoff. The takeoff Speed Vr is calculated as Indicated Airspeed. Imagine you have a Headwind Component of +50. You Groundspeed would be way lower than your Airspeed. What counts is the amount of air that flows over the wing in order to takeoff, not the speed relative to the ground.
answered 11 hours ago
WindshearWindshear
1113
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered 11 hours ago
WindshearWindshear
1113
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered 11 hours ago
WindshearWindshear
1113
answered 11 hours ago
WindshearWindshear
1113
1113
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Windshear is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
Steve is a new contributor. Be nice, and check out our Code of Conduct.
Steve is a new contributor. Be nice, and check out our Code of Conduct.
Steve is a new contributor. Be nice, and check out our Code of Conduct.
Steve is a new contributor. Be nice, and check out our Code of Conduct.
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21
$begingroup$
It seems you are a commercial pilot working at an airline and being trained on a new aircraft type. If that is true, I find it hard to believe that you don't understand the difference between indicated airspeed and ground speed.
$endgroup$
– Mike Sowsun
9 hours ago
2
$begingroup$
What airplane are you flying that has a groundspeed indicator?
$endgroup$
– Wirewrap
7 hours ago
3
$begingroup$
@MikeSowsun Sad (and scary) but all too common (bell curve effect?) I once knew a commercial pilot who had to ask why potato chip bags burst when taking them up from Denver (elev ~5000 ft) to a ski resort at 11,000 feet in the Rockies.
$endgroup$
– Jim Garrison
6 hours ago
2
$begingroup$
@Wirewrap Every GPS I've seen displays current ground speed. In a glass cockpit, it's often put near IAS/TAS on the screen, unlike in a six-pack layout.
$endgroup$
– StephenS
6 hours ago
$begingroup$
@Wirewrap in a glass cockpit the GS will be with navigation data, not with primary flight display data like the speed tape, because ground speed is a navigation related data point, not a flying related data point.
$endgroup$
– John K
5 hours ago