Tail wind effect on Airliners
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Tail wind effect on Airliners
Good morning ,
I hope this question wont be seen as stupid but I cannot quite understand the following ,
Recently flew to Cyprus ex Man to Paphos on a Thomson 767 wide body thing,- 2 seat aisle 4 seats and then another two seats. Huge winglets and big engines with much take off thrust.
The seat back tv screen had a scrolling route and fed information about the height , ground speed and wind speed, plus compass headings. and outside Air temp , the trip was very quickly over with a flight of 4.5 hours
I am struggling to work this out Tail wind advised at 36K ft as 117 mph ground speed advised at 612 mph, to some of you this may sound a daft question but at what speed would that sort of A/c fall apart, or is the aircraft structure only actually feeling the effect of traveling at ground speed less tail wind..?
The flight was also super smooth not a jot of turbulence, apart from a sort of Slam Dunk landing at Paphos!
Peter R-B
Lancashire
I hope this question wont be seen as stupid but I cannot quite understand the following ,
Recently flew to Cyprus ex Man to Paphos on a Thomson 767 wide body thing,- 2 seat aisle 4 seats and then another two seats. Huge winglets and big engines with much take off thrust.
The seat back tv screen had a scrolling route and fed information about the height , ground speed and wind speed, plus compass headings. and outside Air temp , the trip was very quickly over with a flight of 4.5 hours
I am struggling to work this out Tail wind advised at 36K ft as 117 mph ground speed advised at 612 mph, to some of you this may sound a daft question but at what speed would that sort of A/c fall apart, or is the aircraft structure only actually feeling the effect of traveling at ground speed less tail wind..?
The flight was also super smooth not a jot of turbulence, apart from a sort of Slam Dunk landing at Paphos!
Peter R-B
Lancashire
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The aircraft "feels" only its speed through the air. So in your example the airspeed was about 500mph (ground speed minus the tail wind).
Thinking about it another way, the aircraft has no knowledge of the ground so doesn't mind going fast when its got a tailwind.
Think about rowing a boat up or downstream in a river, or walking backwards or forwards on a travalator. Its the same thing.
Thinking about it another way, the aircraft has no knowledge of the ground so doesn't mind going fast when its got a tailwind.
Think about rowing a boat up or downstream in a river, or walking backwards or forwards on a travalator. Its the same thing.
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IAS is Q and is what the aircraft feels.
TAS is how fast you're actually travelling through the air mass.
GS is TAS +- wind component.
At a rough guess your IAS would've been 260-270 kts in the cruise. Probably lower than the IAS in the climb.
TAS is how fast you're actually travelling through the air mass.
GS is TAS +- wind component.
At a rough guess your IAS would've been 260-270 kts in the cruise. Probably lower than the IAS in the climb.
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You are confusing airspeed and groundspeed. Groundspeed is entirely irrelevant to an aeroplane except as far as navigation is concerned. It does not affect flight one iota.
Many non-pilots find this hard to grasp, especially model flyers, some of whom are convinced their model gains airspeed on turning into wind, and loses it turning downwind!
I used to take a chap in the back of the Chipmunk who swore he could tell when we had a tail wind by the increased blast of cold air coming in under the back of the canopy!
Many non-pilots find this hard to grasp, especially model flyers, some of whom are convinced their model gains airspeed on turning into wind, and loses it turning downwind!
I used to take a chap in the back of the Chipmunk who swore he could tell when we had a tail wind by the increased blast of cold air coming in under the back of the canopy!
