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.


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 ...


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 ...


25

I think it was for two reasons: It makes for straight path for the controls to reach the engines, as all of these are fly by cable. Many of these aircraft where also designed for harsh climates, so I imagine it's an advantage to have less pulleys and other things which might rust and require maintenance. There is very little space to place the throttles ...


24

The key in holding the same speed as your wingman or the other aircraft is not to find the "perfect" throttle position, the key is to slightly adjust the throttle. When you look at cockpit-videos of those formation pilots (like this - move the camera to the throttle, it's a 360-degree video), you can see that they are constantly moving the throttle. They ...


24

This setup was actually pretty common for four-engine aircraft of the day. Look at the cockpits of airliners from DC-4 to Lockheed Constellation, and you'll always see a dedicated flight engineer station -- not to the level of managing throttles (which would require a voice command from the PIC to change power setting, impractical for the reaction times ...


21

I've examined a Lazair, and actually taxied one around on the ground once, and yes there are two throttles. Two reasons: In any twin engine airplane you want to minimize or eliminate single-points-of-failure (especially with engines as unreliable as little 2-stroke water pump motors) and this means you want the keep each power plant completely mechanically ...


20

There are a few ways rough throttle handling on a propeller airplane can get you into trouble: Gyroscopic yaw and torque: a rotating prop creates yaw 90 degrees to its spin which are offset by control inputs (mainly rudder), throttling up or down requires changes to these control inputs. Quick changes require bigger changes, slower changes give a pilot more ...


19

The reasons presented at ground school for the benefits of de-rated thrust takeoffs were twofold: less chance of catastrophic engine failure during takeoff less overall wear between overhauls It is from this standpoint that reduced thrust takeoffs are safer. As you point out, these are only authorized when the weights, temperature and runway length allow,...


17

Overhead throttles are a pretty common thing in seaplanes (see the picture in Manfred's answer). This actually came up as an EAA Young Eagles FAQ and in addition to the reasons Manfred gave the Grumman engineer they spoke to gave an explanation I'd not heard before: …first and foremost, the reason the throttle are overhead is due to a physiological issue ...


15

While turning the nose gear is the primary means of turning while taxiing, differential thrust can be used when necessary. Offhand I can think of three instances where differential thrust should be used on an airplane such as the 747: If for whatever reason you are taxiing very slowly, and you're on narrow taxiways and need to make a 90 degree turn, you'll ...


15

14 CFR 23.673 - Primary flight controls defines primary flight controls as: Primary flight controls are those used by the pilot for the immediate control of pitch, roll, and yaw. While a throttle could be used to effect changes in aircraft attitude (depending on configuration and other factors), the effect could hardly be called immediate/direct. So, ...


15

Most likely this is happening after the pilot advances the power lever -- but the power lever controls both throttle (fuel flow, in a turbine), and propeller pitch. The propeller can change pitch pretty quickly, while the turbine takes longer to increase power (increased fuel flow must produce hotter combuster air, which must then spin up both the turbine-...


15

This image would suggest it had two throttles, located in the usual position on the pilot's left side:


13

Actually he does push the button before selecting takeoff thrust. Often1 the procedure on jets during take-off is to move the thrust levers about half way, wait for the engines to spool up and only then select TO/GA or Flex thrust as desired. In the video the pilot switches the display during this intermediate step. So the engines are not even spooled up ...


13

In a constant speed prop, the prop control lever basically changes the speed of the prop (it is not always running at the same speed as you indicate in your question, but rather once the speed is changed by the prop control lever, the governor keeps it at that speed). If power (or airspeed) is changed, the blade angle will automatically change in order to ...


12

This actually happened to me about two months ago. On a very cold night, I went to do my night-currency (3 takeoffs and landings) in a Cessna SkyCatcher (C-162). The plane was hard to start due to the freezing temperatures, but eventually got it going. I did the normal run-up checks, took off, and did one loop around the pattern, coming back for a normal ...


12

As far as I understand, the JAL123 pilots did use thrust manipulation in an attempt to control their crippled aircraft -- however, Japan's largely mountainous terrain conspired against them, as trying to figure out fly-by-thrust-lever requires a massive quantity of airspace, and unfortunately for JAL123, there was a mountain in the way of that effort. ...


12

Yes, The Northrop Grumman B-2 Spirit Stealth Bomber. The leading edge of the wing has an internal structure that helps it absorb radar energy. The outermost wing segment features a "rudderon" or "deceleron", a vertically-split airbrake / rudder that simultaneously opens up and down. To act as an airbrake, both the decelerons are opened, while to ...


12

On a carbureted engine, the mixture and throttle setting does not affect prime, which uses a separate injection system that draws fuel into a syringe and injects it into the intake passages at the cylinders when you push in the primer's syringe plunger. On a fuel injected engine, where the Bendix mechanical fuel injection system is pretty common, if the ...


11

An airline policy of doing reduced thrust takeoffs is considered to improve safety in the longer term by reducing the probability of an engine failure, due to reduced cumulative wear on the engines and reduced engine stress during each takeoff. The primary motivation for reduced thrust takeoffs however is cost. Engine life can be significantly extended by ...


10

All multi-engine airplanes, whether jet or prop driven have separate throttle controls for each engine. There are good reasons for this: If there is a problem with one engine you can separately control it for troubleshooting purposes If one engine isn't developing the right amount of power you can independently increase the other engine(s) to compensate If ...


10

Control means to be able to vary the forces which act on an airplane, both longitudinally and vertically. Ideally, any variation will create an immediate feedback, so the pilot can "feel" how much more action is needed for the desired change. If, however, the variation of forces builds up slowly, the dynamic answer of the airplane will make the closing of ...


9

Flaps in a C150 (and pretty much any type) take a few seconds to move. Throttle change is more-or-less instantaneous. If you were to throttle up first, and then change the flap position there is a good chance that you are lifting off while the position of your flaps are changing. This is not a good idea, changing the amount of lift generated by the wings in ...


9

When you start the engine in the c172, the blades on the prop are spinning - but the plane doesn't move at all. When the propellor is idling its obviously moving air, this you can see, feel, and hear, however its simply not spinning fast enough to provide enough thrust to overcome the force of the plane sitting on the ground. Basically this is comprised ...


9

Note: Below is valid for applying takeoff thrust (part of the question), but it's now evident it wasn't the takeoff being shown in the video. Refer to OSUZorba's answer. According to the video description, that B-52 belongs to the 2d Bomb Wing, which operates the B-52H variant. According to the declassified B-52H manual, the pilot flying should advance all ...


7

As others have stated, it is possible to control a plane using throttles alone, assuming the control surfaces are largely neutral and the plane is at an stable attitude (e.g. not spinning or stalling): To climb, increase throttle of all engines To descent, decrease throttle of all engines To turn, decrease throttle of engines on the inner side of the turn ...


7

The video shows the pilots starting the engines. The typical engine start procedure on the B-52, either engine number 4 or 5 is started first. This video shows them starting engine number 5 first. Once number 5 is running, you cross bleed air to engine 4, starting it. Once number 4 and 5 have stabilized at idle for 2 minutes, the other engines can be started....


7

(Above is the max cruise limit in standard ISA for the A320.) It's 80.4% - 86.5% for the different weights and altitudes. Do note that 81% does not mean 81% of the available thrust. The maximum continuous thrust (MCT) at standard temperature is between 86% and 89% for the different cruise flight levels. The colder the air, the lower the values, and vice ...


7

Some of the early radial engines that operated by rotating the entire engine along with the prop, specifically, the very popular Le Rhone didn't have proper throttles. The pilot controlled engine speed by switching the ignition on and off. This wasn't so much a limitation of that particular design, as a limitation of engine tech in general at that time. ...


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