Hot answers tagged

126

Years ago now I gave a fair amount of instruction for seaplane ratings. I remember it quite fondly as seaplanes combine the fun of flying with aspects of the fun of boating. There were three conditions in which we used curved takeoff runs. The most frequent curved takeoffs were on rivers, which tend to not run in a straight line, and even for those portions ...


92

Yes, The HMS M2 had a single seaplane aboard that it was capable of launching. Her 12-inch gun was removed, replaced by a small aircraft hangar, the work being completed in 1927. This could carry a small Parnall Peto seaplane, specially designed for the M2, which, once its wings had been unfolded, could be lowered onto the sea alongside by a ...


86

V1. There are other valid reasons, as have been listed - cost, bidirectional runway use, etc. These would still not completely disqualify ramps, just limit them to very special circumstances. But the one disqualifying factor is that a ski jump takeoff removes the necessary element of safety airliners depend on during takeoff. Up to a certain airspeed, ...


81

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!


72

The reason was to give the bombs the place close to the center of gravity. Wing sweep (for high cruise Mach numbers) in combination with a high aspect ratio of the wing (for low induced drag) made it impossible to place the landing gear in the wing, so it had to be integrated into the fuselage. The main landing gear normally needs to be close to the center ...


69

I've heard about lots of bird strike incidents that occured during a takeoff roll or the early phase of takeoff climb but hardly heard of bird strikes on approach or landing. This is always a dangerous thing. Only because you hear more bird strikes that occur on takeoff, it does not mean there are more at takeoff. I found, for example, this report about ...


64

What you are hearing is "V-One", written as V1. It actually is said when they can no longer safely abort the takeoff with the remaining runway, but they still are not quite ready to takeoff. As they get a little faster, there should then be a second callout of "Rotate" when they have achieved the required takeoff speed, and that is when they actually ...


64

Living Wing The Super Hornet has a living wing, that is to say, the shape of the wing is constantly in motion throughout every regime of flight. Trailing edge flaps, leading edge flaps, stabs, rudders, and ailerons all move in concert to give the pilot the greatest control during particular phases of flight. This is evident by the use of the flaps switch. ...


53

Adding to the excellent Peter's answer who explained why for this particular model the wheels are placed far behind the centre of gravity (CG), I would like to clarify why this makes impossible to rotate at take off. A standard aircraft takes off right after the rotation, increasing the angle of attack and the lift. Before and while performing the rotation ...


50

That could end up being a really bad idea if you've accelerated past your V1 speed -- your abort would then put you off the end of the runway, and the consequences from that range from bad to catastrophic. A much better idea would be to look at the markers on your airspeed indicator, and if you're at/above rotation speed, go ahead and rotate. Then sort out ...


48

Because then you can only land in one direction. What do you do if the wind blows exactly along the runway so that departing and landing planes have only tailwind then? You would waste a precious runway by having such a big obstacle on it. Moreover, an upward ramp might not be what is needed. Look for example at Lukla (or, as ManuH mentions in the ...


45

I flew for two 747 carriers that never bought new aircraft, and thus this answer applies to 747-100/200 aircraft as originally manufactured for a number of different airlines. The tiller is active when the aircraft is on the ground and the nose gear is compressed regardless of groundspeed as I remember. I've never heard of a pilot accidentally hitting it ...


43

Let's see what the savings are: A mid-sized airliner carries maybe 20% of its mass in fuel. This fuel has an energy density of 43 MJ per kg. Of that chemical energy at most 40% is converted into useable work. Heck, let's make this 25% so we are really conservative. Thus, the energy for the whole trip is $$E_{\text{trip}} = 0.2 \cdot 0.25 \cdot 43,000,000 \, ...


43

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 ...


41

No, the gear doesn't actively extend, and any passive change to the strut extension during takeoff is likely to be imperceptible. What you are perceiving during takeoff is the somatogravic illusion. It is a physiological sensation, not a physical change. Rapid acceleration, as during a takeoff roll, causes the inner ear to report what your brain assumes is ...


41

Fully permitted according to this Configuration Deviation List for the A320: One fairing may be partly or completely missing. There are more posts about this occurring. As Noah Krasser points out, it looks fairly dodgy to observant passengers. This is the "Master" list, i.e. the safe and approved baseline. Some airlines may have changes in their own ...


41

When the brakes are on, they apply a backwards force that counters the engine thrust. This force is applied at ground level, and the engine thrust is higher. These two forces result in a moment that forces the nose down, compressing the nose gear slightly. When the brakes are released, the moment disappears and the nose gear extends. Another factor here is ...


40

The Aviation Safety Network has an article listing 11 airplanes that crashed after being stolen by a non-pilot. The most recent was the Horizon Air Dash 8 that was stolen by a ground service agent in August 2018. There are more interesting stories such as: The guy that tried to crash a Cessna 150 into the White House (with minimal experience and training) ...


39

No. Firstly, as a comment noted, the takeoff was hardly "near vertical", the camera angle makes it look so. The takeoff angle in the video certainly is much steeper than a normal one, but Airbus aircraft are more than capable of doing the same - in fact an A350 did very much the same thing at the Paris Air Show. The notion that an Airbus doesn't let the ...


38

Forward flight is much more efficient than hovering. As airspeed builds, lift increases from "translational" lift as the air moves more horizontally over the disc. Since the relative airflow is more horizontal, the angle of attack for a given pitch angle is increased. The vortices and turbulence move behind and down from the helicopter so undisturbed air ...


38

That's a weight check. The sign has the weight of the aircraft in pounds. The catapult crew guy first shows the presumed weight to the PIC who must give a thumbs up, agreeing, "Yes, that is the weight I believe my aircraft to have." The crew guy must then show the same exact set of numbers to the catapult chief operator, who must also approve it: "Yes, the ...


38

These are secondary intake doors which allow more air to reach the engines. They are opened by the engine control computer when the main intakes are not providing enough air for the power setting of the engine. In order to minimize radar cross section, the engines of the B-2 are buried in the wings and the intake needs to be curved. Also, and for the same ...


37

It happens when the airplane levels off after takeoff, usually either at the first assigned altitude or at a safe altitude where it will be accelerated in order to retract the flaps. The feeling is a result of negative vertical acceleration. It can also happen at other times during the flight, such as during turbulence or when starting a descent. ...


37

There are several kinds of power reduction which could happen after takeoff: Cutback (noise reduction when the airplane is very low, after takeoff) Climb thrust Both are set on the CDU (Control Display Unit, the screen and keyboard of the FMC, Flight Management Computer). Since you describe a temporary and dramatical power decrease, this should be the ...


36

Let us consider the operations other than takeoff on runway 18. Takeoff Runway 36 There are buildings not far off the departure end and directly after the end of the runway is a movement area and ramp. To safely takeoff they would have to clear that area and probably replace all the concrete with crushable concrete (more on this later). The buildings ...


36

Because the pilot is taxiing the airplane with the props in the beta range (turboprops turn into landsharks if you don’t do this and you end up really riding the brakes to keep the speed down), then on takeoff, the propellers move into a maximum power setting, the engine snarls and slows a bit under the increased workload.


36

It exists for some aircraft carriers and it's called a ski-jump. It wouldn't work well for land runways because they're typically used from either end depending on the wind. Moreover, land planes don't use the whole runway, failures notwithstanding, they takeoff before the end and by regulations must clear a certain height before the end (depends on the ...


33

The balloon is spread out on the ground and rigged to the basket. Then, a cold air blower is used to do the initial inflation, blowing air into the envelope through the bottom aperture. This gets the balloon about 75% inflated, but still horizontal. Lastly, the burners are lit to heat the cold air already inside the canopy, expanding it and raising the ...


32

it is not obvious if it could alter the wing shape for this to be a problem It may not be obvious but it is so. Plain old snow will just blow off as soon as the plane picks up speed, but if the wing was above freezing when the snow first fell on it, the snow will probably conceal a layer of rough ice, which will not blow away. Anything adhering to the ...


32

It's because he was taxiing in DISC (discing, or flat pitch making the prop like a big disc), which is in the ground beta range, then coming out of it. Beta range is a mode where propeller blade angle is directly controlled by the power levers, and the propeller RPM is controlled by an Np governor in the fuel controller modifying gas generator (the engine ...


Only top voted, non community-wiki answers of a minimum length are eligible