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Ground speed is the horizontal speed of an aircraft relative to the ground. An aircraft heading vertically would have a ground speed of zero. Information displayed to passengers through the entertainment system often gives the aircraft ground speed rather than airspeed.

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What is wrong with a high-speed landing for an ultralight or GA aircraft?

Is it okay to land an ultralight or a general aviation plane at a speed higher than the recommended landing speed for such plane? Will there be any damage if the descent rate is very low?
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1answer
198 views

Calculating Ground Speed - E6B vs Pythagorean Theorem

I have been trying to create an excel formula for calculating the ground speed of an airplane using the TAS, Course, Wind Dir, and Wind Velocity. The issue that I am finding is that I can't properly ...
1
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1answer
118 views

What is the unit for ground speed reported by ADS-B?

Strangely enough, I'm having trouble finding the unit reported by ADS-B on the Internet. Many sites simply refer to it as "ground speed". Is it measured in KPH?
6
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1answer
292 views

What special tyres (tires) are needed for high altitude takeoff and landing?

I just watched this video of AA922 taking off from El Alto (LPB) to Santa Cruz. The video's author mentions that the aircraft needs "... special tyres" due to the high altitude. While I do ...
2
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1answer
142 views

What is the name of centre of mass speed of an aircraft?

I have a list of positions (X [NM], Y[NM], Z[NM]) of an aircraft. Every coordinate is given every 1 second. I calculate the speed [knots] between two consecutive coordinates in the following way: $...
4
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2answers
390 views

Why did the speed of this plane drop so much? [closed]

(Disclaimer: I know nothing about aviation. It is not even a hobby to me. I'm sorry if this question sounds obvious or silly to experts.) I was casually checking the arrival time of a flight on ...
8
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2answers
12k views

How to calculate the real Ground Speed from True Air Speed?

In most of the formulas I've found online GS = TAS + Vw, i.e. true air speed plus wind. However, on the simulator, GS changes drastically if I dive or climb which is obvious because I'm covering 0 ...
1
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1answer
81 views

What is the groundspeed history of an aviation of such as a Boeing plane? [closed]

I would like to see groundspeed data of civil aircraft for distances such as 300 miles. What could it look like for a popular model such as Boeing 737?
6
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2answers
886 views

Does ground speed represent the horizontal speed measured at sea level?

Which of the following vectors is refered to as the Ground Speed? The green one I expect is TAS, the blue one would be Vertical Rate Note that for simplicity I did not draw them as geodetic curves, ...
1
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2answers
3k views

Is there a formula to calculate ground distance traveled given rate of climb and true airspeed?

I'm looking for a formula to calculate the horizontal distance (guess it is the Ground Distance) passed during the phase of ascent (or descent), having the rate of climb in ft/min and the TAS in knots....
2
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3answers
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Why do we need to know both groundspeed and airspeed? [duplicate]

As far as I understood it correctly: airspeed: is obtained by measuring the difference in airpressure (using Pitot tubes I guess?) around the aircraft and the airpressure caused by propulsion. ground ...
1
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3answers
279 views

Where does the difference between calculated and actual groundspeed come from?

I'm a paragliding pilot. At school we learn that the trim speed of a paraglider is about 38km/h airspeed, the accelerated airspeed is about 45km/h and the minimum airspeed is 22km/h - being inside the ...
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6answers
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How do head- and tailwinds affect airspeed?

I'm sure this was asked somewhere, I just can't find it. So if it's a dupe, let me know. Anyway, I'm one of those guys that actually looks at the flight information when I'm flying. I fly ...
23
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1answer
3k views

How much leverage do commerial pilots have on cruise speed?

If you fly frequently there are chances you have seen some delays in departure where you end up waiting in the aircraft sometimes for multiple hours. Almost every time that happened I remember the ...
5
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2answers
969 views

How do pilots manage the speed during the approach?

Once the initial approach fix is reached, what are the different "speed stages" to the runway? I often read about landing speed and approach speed. For example on this chart, Boeing indicates ...
4
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1answer
1k views

How is TAS affected by wind?

Does True Air Speed (TAS) change with wind speed and direction? My understanding is that if an aircraft were travelling at 470kt TAS, with a hundred knot tailwind, the ground speed would be 570kt. In ...
24
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13answers
9k views

How did planes measure their speed relative to the ground before GPS?

How did planes measure their ground speed before GPS? If they used some sort of anemometer to measure speed, that would only measure the speed of the plane relative to the air through which it is ...
16
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5answers
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Why does the speed of commercial airliners fluctuate, sometimes as high as 1,060 km/h or as low as 800 km/h?

I've noticed that (long-haul) airliners sometimes travel at as high as 1000 km/h (I believe I've even seen 1040 km/h), but usually they fly closer to 800 km/h, for most of the trip. This seems odd ...
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2answers
458 views

Is it centrifugal force that allows a non-aerodynamic body to achieve lift purely because of thrust? [closed]

If a body has a greater than one thrust to weight ratio, then is the centrifugal force acting perpendicular to the Earth's gravitational pull that allows it to fly ? Or are there other forces that I ...
2
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1answer
1k views

What is the difference between ground speed and airspeed? [duplicate]

What is difference between ground speed and airspeed? Is ground speed used only for takeoff or is it used for flight too?
13
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2answers
1k views

What could cause an irregular climbing pattern on takeoff?

Yesterday (Dec 21, 2015), I was on board Ryanair flight FR4966 from London Stansted (STN) to Lamezia Terme (SUF). The aircraft was a Boeing 737-800, registration EI-EFW. On takeoff, the climbing ...
7
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1answer
1k views

Why did the Flightaware groundspeed readout suddenly spike for this flight?

My 18yr old son is currently in Barcelona - first time abroad and in a plane. Being an overprotective parent I thought I'd track his flight so I could see when he had landed safely = and save the data ...
2
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0answers
185 views

Why do planes accelerate when they touch down on a aircraft carrier [duplicate]

I was watching a plane documentary, and when the part about aircraft carriers came on, I noticed that as soon as the plane hits the aircraft carrier runways, the plane speeds up. Why is this happening?...
15
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3answers
4k views

How is the actual ground speed of an airliner measured?

Do pilots have the "ground speed" information available? If so, how is the ground speed measured? Or do they rely on GPS info to calculate it?
14
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7answers
17k views

Why is tailwind during final approach and landing so dangerous?

I understand that tailwind is typically a good thing during your flight as it increases your ground speed and gets you to your destination faster. Despite that I get a feeling that pilots typically ...