95 votes

What is the slowest fixed-wing airplane?

The Gossamer Albatross is a human-powered plane with a top speed of 29 km/h (18mph). It was used to cross the English Channel and seems to meet the criteria of the question.
Michael Schumacher's user avatar
83 votes

Why is indicated airspeed rather than ground speed used during the takeoff roll?

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!
Harper - Reinstate Monica's user avatar
65 votes
Accepted

Would a slower speed and lower altitude reduce fatal incidents?

I'd like to answer this question by debunking the premise of the question: that most plane crashes happen when planes fall out of the sky, and that it's like rock climbing where the higher you are, ...
Cody P's user avatar
  • 6,775
62 votes

What is the slowest fixed-wing airplane?

The Antonov AN-2 has no stall speed quoted in the operating manual and can fly under full control at about 30 mph. Thus if the headwind is sufficiently large the aircraft will move backwards with ...
Brilsmurfffje's user avatar
61 votes

Would a slower speed and lower altitude reduce fatal incidents?

It would likely create a more deadly situation. In aviation altitude is your friend. Generally speaking altitude in the case of an emergency buys you time to work the problem. Generally you want to ...
Dave's user avatar
  • 101k
47 votes

What is the slowest fixed-wing airplane?

The Harrier, Yak-38, Yak-141, XV-15, and V-22 are all fixed wing aircraft. All can hover in mid air, controlled. So they are in controlled flight at 0 velocity. At least the Harrier can even be in ...
jwenting's user avatar
  • 15.9k
43 votes
Accepted

What happens if you exceed the maximum speed on a C172?

You can, but you have to live with the consequences. There are several things that can happen: Depending on the vertical gusts ahead, you might not even get close to v$_{NE}$. There is another speed ...
Peter Kämpf's user avatar
43 votes
Accepted

What is a jet (unit) shown in Windows 10 calculator?

It is not a unit. It is just Microsoft trying to be funny. Or to convey an idea of the magnitude. Thanks @Jackie for pointing out that around March 2019, Microsoft has released this calculator as ...
bogl's user avatar
  • 10.7k
43 votes

Why is indicated airspeed rather than ground speed used during the takeoff roll?

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 (...
DeepSpace's user avatar
  • 4,495
43 votes
Accepted

What is the commercial passenger aircraft top speed record?

"Speed" is not a singular term in aviation. There are many different ways to measure speed. See for example Why is there a difference between GPS Speed and Indicator speed? Most commercial jets cruise ...
60levelchange's user avatar
39 votes
Accepted

The SR-71 flew at 2193 mph. Mathematically, how can this be Mach 3.3?

The SR-71 was only capable of Mach 3.3 flight at altitude. You can see the limitations in the pilot's operating handbook(POH) for the aircraft: At higher altitudes the relative speed of sound is ...
Dave's user avatar
  • 101k
36 votes
Accepted

Can a helicopter really fly with rotors going this slow?

It's an illusion that the blades appear to be going slowly. It's actually a well known effect called the wagon wheel effect. Essentially the rotor is spinning at close to an even multiple of the ...
ratchet freak's user avatar
33 votes
Accepted

Do Air Traffic Controllers have to remember stall speeds for different aircraft?

No because aircraft are categorized by their speed at the runway threshold (1.3 times stall speed). VAT —Speed at threshold used by ICAO (1.3 times stall speed in the landing configuration at maximum ...
mins's user avatar
  • 71.8k
31 votes

How does it feel like to be outside a flying airplane?

It won't be pleasant. The main result of being exposed outside at altitude, besides the obvious hypothermia, frostbite and hypoxia, will be bruising from the 280-ish knot slipstream (it's the ...
John K's user avatar
  • 130k
30 votes
Accepted

Does a sudden drop of the velocity of the headwind affect the airspeed by lowering it?

Your airspeed does not remain constant because of inertia: it takes more time for the airplane to adapt to the new relative wind, compared to the time it takes for the wind to change. Example One: ...
kevin's user avatar
  • 39.7k
30 votes

Why would 2 aircraft fitted with the P&W PT6 Engine have different top speed?

The P&W PT6 comes in many different varieties. The smallest PT have 500hp while the largest have 1700hp. It is not the "same engine" as you state in your question. The standard Caravan has ...
Mike Sowsun's user avatar
  • 37.7k
29 votes

What is the commercial passenger aircraft top speed record?

Other than the TU-144 and Concorde, the record for the fastest True Airspeed in an airliner probably belongs to a DC-8. Wikipedia Douglas DC-8 On August 21, 1961, a Douglas DC-8 broke the sound ...
Mike Sowsun's user avatar
  • 37.7k
28 votes
Accepted

Why is a 737 Original speed-restricted below 10 kft with inoperative windscreen heating?

To reduce damage in case of a bird strike. The restriction is not only for the 737-100 and -200 models, the 737 NG QRH says: WINDOW HEAT OFF In flight: WINDOWS HEAT switch (affected window) ..... OFF ...
Bianfable's user avatar
  • 55.4k
25 votes
Accepted

Why must Vr be set so precisely?

This answer is written for air transport category aircraft. Introduction During take-off there are three operationally significant speeds that ensure a safe take-off: V1 - the take-off decision speed ...
DeltaLima's user avatar
  • 83.1k
24 votes
Accepted

What is the reference used when measuring flight speed?

Speed of a plane is actually measured in a number of different ways, and relative to different things. Here is a summary of the different types: Indicated Airspeed (IAS). This is the number shown on ...
DJClayworth's user avatar
  • 3,728
23 votes
Accepted

What is the reason for changing the speed reference (IAS or Mach number) with altitude?

Aircraft are limited by both air speed (VMO, affects loads on the structures) and Mach (MMO, formation of shock waves resulting in buffet). At low altitudes, the speed of sound is high so an aircraft ...
fooot's user avatar
  • 72.8k
22 votes

Why does the speed of commercial airliners fluctuate, sometimes as high as 1,060 km/h or as low as 800 km/h?

There are three different speeds that are of relevance here: Groundspeed- This is probably the speed indicated to the passenger. For them, this is the most relevant as it determines the time taken ...
aeroalias's user avatar
  • 100k
22 votes

Is it right to extend flaps only in the white arc?

Yes you must slow down to the white arc, or whatever your flap extension speed is for a given condition, regardless. If you are 10kts above the white arc and drop flaps anyway, it's not going to make ...
John K's user avatar
  • 130k
22 votes

Why would 2 aircraft fitted with the P&W PT6 Engine have different top speed?

Even if the installed engine version was identical (which, as @MikeSowsun noted, is not always the case), different types have different weights, drag profiles, and may have different propellers ...
Zeiss Ikon's user avatar
21 votes

What is the slowest fixed-wing airplane?

now, if you're looking at modern, more commonly used transportation, powered paragliding would probably take the cake. CC BY 3.0, https://en.wikipedia.org/w/index.php?curid=13110495 Powered ...
tuskiomi's user avatar
  • 556
21 votes

What is the commercial passenger aircraft top speed record?

I think I know what you're asking, and the Concorde-excluded answer is almost certianly the Convair 990 which could get just shy of Mach 1. From wikipedia: The Convair 990A is still the fastest ...
John K's user avatar
  • 130k
21 votes

How does it feel like to be outside a flying airplane?

This is from Irish Luck - Surviving Partial Ejection from A-6 Aircraft. In this incident, the bombardier/navigator's ejection seat came part way out of an A-6, leaving the head and upper body exposed. ...
Eugene Styer's user avatar
  • 3,519
20 votes
Accepted

Is trimming for constant speed equal to trimming for constant angle of attack?

Short answer: Yes Generally you are right. You are trimming the aircraft for a point on its polar, and that point is reached at a specific angle of attack. You say yourself we should neglect ...
Peter Kämpf's user avatar

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