Hot answers tagged

72

It isn't a black and white issue of who has higher authority. A pilot in command (PIC) is the ultimate authority for the safe operation of his airplane. An air traffic controller is the authority for the block of airspace or pavement he controls. When you are operating under ATC, it is your responsibility to comply with their instructions as long as ...


62

Aligning yourself in the middle of a straight taxiway isn't a problem. On the 747, if you put yourself in the middle of the taxiway as you see it beyond the nose, you'll be in good shape. If you're the captain, you can hold yourself a little left of the perceived center, but not much, because you're looking at from an eye level over 30 feet up as I remember. ...


53

This is called Powerback, most aircraft can do it, but it is not done very often. In a jet aircraft, the three main problems are: Reverse thrust tends to throw a lot of debris into the air because the exhaust is deflected to the sides and up and down too. This debris can damage the engine itself, other things on and around the aircraft or injure someone on ...


49

It depends. Some instructions are really simple and with a little practice, are very easy to remember. Runway 27 right, line-up and wait Turn left heading 250, descend flight level 120. Other ones will be so common, they are just remembered: Taxi to Gate 1 via Alpha, Alpha 1, Lima 3, cross runway 24, hold short Delta. But this is where the danger ...


46

The taxiway is being used for parking. Specifically, parking of two MD-80s that have attracted press attention—The Australian: Clive Palmer’s $10m in tax-haven jets sitting idle: TWO 155-seat jets owned by Clive Palmer and branded with the name of his controversial and longtime loss-making company Mineralogy sit mothballed in a remot­e corner of ...


44

(Source: wikimedia.org) Guiding is called progressive taxi and can be requested. A follow-me car can also be used to guide the plane. In some airports the follow-me car is mandatory, along with its fees. In most cases the pilots use charts. Either paper or electronic. Some electronic charts offer a moving map feature, whereby the crew can see their ...


36

Seaplanes mostly have water rudders that are used at lower speeds and are retractable (actually, they tilt out of the water flow). At higher speeds, like takeoff runs and landings, high speed taxis, they are retracted and the primary means of steering is the plane's rudder. Water rudders are connected to the regular rudder pedals. Airlerons can also be ...


35

When you have the thrust levers of, say, a 747 all the way back to idle, the airplane still has enough power to move. In fact, you will have to use the brakes to keep it from taxiing too fast. If you didn't use the brakes, it would finally accelerate to somewhere around 45 knots or so, far too fast for taxiing, but much too slow to take off. At the idle ...


35

There are automated systems that provide the same function as a marshal. They are in place at some airports but not all since upgrades cost money and not all airports may see a use for it. At smaller fields marshals often serve multiple roles aside from just guiding aircraft they may also handle baggage, pump fuel, drive tugs and all the other various ramp ...


34

That "road" is in fact a taxilane, and marked as such on the Paine Field side (note the yellow lead lines marked at the bottom of the image below, you would find on a taxiway). It connects the Boeing plant to Paine Field's "Boeing Ramp" where final prep can be completed before the aircraft are flown off to wherever they're going. The terminology is ...


32

It was tugged to that position via tug. Angle of photo + possibly trying to offset weight, from centerline. These planes are just being stored there. They'll be tugged to another location before they even bother to start them up, and I believe most don't have engines on at present. They are quite close together. (from @ratchetfreak's answer:) Turn the image ...


30

All of the aircraft that I have ever seen have the rudder and braking functions combined into one set of two pedals. To operate the rudder you press on the bottom part of the pedals, so that they slide back and forth on tracks, and to operate the brakes, you press the top part of the pedals so that they rotate towards the floor. The left pedal operates the ...


30

"Judgmental oversteering" means to intentionally not follow the taxiway centerline when turning. It is a technique used on large aircraft to turn on tighter or smaller taxiways. In a sense, it is like driving a long vehicle, such as a truck or a bus. Instead of following the lines on the road, the driver would deliberately overshoot the entry of turn, i.e. ...


29

Turning Radius, as found in a planning document: 28.7m for a Boeing 777-200 34.7m for a Boeing 777-300 Rotating around one a point a bit off the wing to allow both wheels to roll throughout. Minimum Pavement Width 47.5m for a Boeing 777-200 56.0m for a Boeing 777-300 Source Be aware that this is not exactly ideal- visibility from the flightdeck is not ...


29

Quite simple ― use a (special) towbar! Aircraft with such unique front wheels (like the Antonov An-225 Mriya and Lockheed C-5 Galaxy) carry their own towbar around, which is then attached to the tugs for movement. For example, here is the Galaxy's towbar: From left to right: 68th Airlift Squadon loadmasters, Senior Airman Katy Mackey, Master Sgt. Kevin ...


29

A minimum max reverse power speed is often an airplane operating limitation. It's mostly related to FOD (mostly sand grains and small gravel) and on some designs there may be compressor stall issues due to flow disruptions. On the CRJ 700 max reverse is limited to 75kt although you can use up to 60% N1 down to zero speed. On a 900 you have to be at idle ...


28

They simply aren't necessary. Brake lights are on road vehicles because often they travel at relatively high speeds, and follow relatively close to one another. If a driver suddenly slows, the brake lights help provide a visual cue (which grabs the attention of other drivers, and is visible from quite a long distance) that the vehicle intends to slow or ...


27

During taxiing aircraft turn using their nose wheel. The nose wheel is usually hydraulically controlled. The pilot operates it through a tiller. The nose gear can rotate usually quite far, sometimes to almost 90 degrees. At high speeds, directional control is achieved using the rudder pedals. The nose gear is often linked to the rudder pedals, however ...


27

Almost always pilots use a chart, ie a map which shows the airport from the air. Runways are numbered according to their magnetic bearing (runway 22 is roughly aligned to 220 degrees magnetic for example) while taxiways are lettered. As an example see the chart for La Guardia. A pilot would be given a taxi clearance which gives an end destination and a set ...


27

The wheels do not have power - there is no propulsion system linked to the wheels, they just spin freely. Taxiing is achieved by adding just enough collective so that the helicopter starts moving, but not enough to lift it off the ground. A little forward cyclic also help. To slow down, the main wheels have brakes, like fixed-wing aircraft.


26

Was [towing unit or motors in landing gear] ever tested or assessed? Yes. 2014 Main Gear Using the Auxiliary Power Unit (APU) generator to power motors on the main wheels, the EGTS taxiing system allows aircraft to push back without a tug and then taxi without requiring the use of the main aircraft engines. One wheel on each main gear is equipped with ...


26

Helicopter wheels do not have power. Taxiing is accomplished by using the thrust from rotors- for example, in case of CH-47, with rotors at normal rpm, the helicopter will have some forward speed (5-6 kt) with controls at neutral and thrust control rod at ground detent. Steering is usually using pedals (some helicopters have hydraulic steering) and there are,...


24

And here, a Reference from Boeing's 737 FCTM (pdf). Ch2 for ground operations.


24

A "Safety Alert for Operators" (SAFO 09004) from 2/11/09 says "Slow the aircraft to a fast walking speed on the centerline of the landing runway prior to attempting to exit the runway. Taxi at a fast walking speed until parked at the ramp or until aligned with the centerline of the runway for takeoff." Which, of course, isn't a regulation, in this example ...


24

Airbus documentation claims the pilot can see 20° below horizon directly ahead (provided the seat is adjusted as recommended). Given the window of A320 is about 4m above ground, the closest point is about 11m ahead of them. And the nose wheel is more than 2m behind where the pilots sit. In larger aircraft it's of course proportionally further. So it's not ...


24

The aircraft are moved from the factory to the airfield and paint shops on the airfield side over the bridge. The photo shows a 787 Dreamliner being moved across the bridge. Source: airlinereporter.com


24

Airbus aircraft have 3 hydraulic systems (Green, Blue, Yellow). Green is pressurized by left engine, Yellow by right engine, and each one can be pressurized by the other using the PTU. In addition the Yellow circuit has an electric pump. The Blue circuit is a backup pressurized on demand by several means (electric pump and RAT). Each circuit powers ...


23

The question (& other answers) assume an airliner, but since that wasn't specified, I'll chime in for some tail draggers: For some tail wheel aircraft, the short answer is they don't. If you watch a Pitts Special, a P-51 Mustang, a Gee-Bee, or other large engine wheel in the back airplane, you'll see them make a series of "S-turns" as they taxi. The ...


23

It is not a road that you are looking at, it is the edge of the runway / taxiway. The double yellow lines are used to define the taxiway edge from the shoulder or some other abutting paved surface not intended for use by aircraft. The blue lights in the yellow boxes are taxiway edge lights. The poles next to the lights are blue reflective markers that ...


23

No, there is no mandatory stop. Typical clearances given before departure are: BigAir 123, hold short of runway 36. BigAir 123, line up and wait runway 36. Former phraseology in the US was "position and hold". BigAir 123, behind landing A320, line up and wait runway 36, behind. Note the word "behind" being repeated at the end of the clearance. ...


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