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4

In the US, the department of commerce had an Aeronautics Branch. It was first responsible for civil aviation safety. On February 28, 1927 it published a list of the first physicians, who were qualified to give medical examinations for pilot licenses. On December 31, 1926, the Aeronautics Branch issued the first air commerce regulations, that included ...


-1

Yes. Airworthiness Directive 2012-13-5 also known as Boeing service Bulletin 777-35A0027. And there is much more info. AD 2012-13-5 replaced oxygen supply lines on all 777, many 767, 737, and 747. The lines contained spiral wires for anti-collapse and were not insulated on the ends. It was a subcontractor fault. The spiral wire conducted mili-volts. ...


-1

Missles are way too fast for a commercial jet to take evasive maneuvers even if it was capable of it. Korean Air 007 in 1983 is a perfect example of pilots not knowing about missiles. They strayed into Soviet Airspace (unknowingly) and the pilot that shot the plane down suspected it was a commercial plane built by Boeing but shot it down anyway. He ...


2

Wouldn't it be better to use no flaps, and rotate at the higher speed that is required? Well, now we are talking about a short field take off. If you ever watched Lindbergh's takeoff the day of the famous journey across the Atlantic non-stop flight, barely clearing a power line on climb out, or even actually done one off a muddy or snowy runway, you know ...


2

Because without flaps extended there is less safety margin for stalling in the landing. Picture above from this answer shows the lift coefficient as function of the angle of attack. With flaps extended, a certain amount of lift is reached at a lower AoA than without flaps. It is a safety feature during landing, when speed needs to be reduced as much as ...


7

Increasing the flaps does increase the drag, but not by that much initially. For the first stages of flaps you gain more by reducing required takeoff speed. If you would increase the flaps more and more, eventually the drag would become too much and you would lose takeoff distance again. Flap setting has an affect on the wing’s lift coefficient and on the ...


0

I don't know if your question relates to the approach phase or the flare. The later as explained above has to do with the elevator, the former i.e for the approach phase you will notice that airliners and even more so fighter jets come on the approach indeed with a high noze up attitude. That has to do with swept wings. Swept wings allow an aircraft to fly ...


7

The change in pitch during the landing is called the flare and it is controlled by the pilot (or autopilot for an autoland) using the elevators (i.e. pulling on the yoke). From the Boeing 737 NG FCTM (6.10 Landing): When the threshold passes under the airplane nose and out of sight, shift the visual sighting point to the far end of the runway. Shifting ...


0

For landing an airplane has to slow down. When looking at the lift equation, $$L=\frac{1}{2}c_L(\alpha)\rho v^2A$$ We find that, to get constant lift $L$ with lower speed $v$ we need to increase either $c_L(\alpha)$ or wing surface area $A$ (we can't change the air density $\rho$). Note the explicit dependency of the lift coefficient on the angle of ...


0

Flaps help to increase the lift at low speed, allowing the aircraft to fly at a lower than cruise speed speed. The pitch up is caused by the elevator on the rear wing.


1

To create a lift, the airflow speed on top of the wings should be higher than the airflow speed on the bottom of the wings. That is correct. Lift is the result of a pressure difference between upper and lower side, and pressure is proportional to the inverse of speed squared if no energy is added. But when you keep the engine on the bottom of the wings, ...


1

No, because the air is still turning the same way. It might even help a little bit, depending on the wing shape. To create lift you need lower pressure above the wing than below, but the difference in speed is the effect, not cause of this. The cause is that the air would like to continue moving straight due to inertia, and the pressure decreases above ...


6

To create a lift, the airflow speed on top of the wings should be higher than the airflow speed on the bottom of the wings. No, that's not true. In order to create lift, the pressure on top of the wings must be lower than the pressure on the bottom of the wings. The airflow speed doesn't matter. I'm guessing your thought process is something like this: ...


4

You're going by an old outdated lift theory, still taught in a lot of places. The wing induces a very large package of air to move down as it's going along, and this newtonian action/reaction of this package of air being induced to move down is most of "lift". The Bernoulli part is important, because the pressure differential is a factor and it also is ...


3

For some general reasons, see Why is engine No.2 started first, instead of No.1? Airbus A350 Specifically to the Airbus A350, I could not find any reason why one engine must be started first. As far as I know every modern airliner could start engines in arbitrary order. The Airbus A350 has two hydraulic systems. From the Airbus A350-900 Flight Deck and ...


3

LAND IMMEDIATELY Continued Flight may be more hazardous than Ditching or Forced Landing LASAP Land as soon as possible at which a safe landing can be made or is assured ANSA Land at nearest suitable approved airport Land as soon as Practical Extended flight not recommended. Landing airfield and duration of flight are at the discretion of the pilot. ...


0

Developing an aircraft (or really any complex system) is not like someone sketches an aircraft and then some people build it, fly it and then more aircrafts are built. You start with making concepts, then designs, which are prototyped or simulated. Then these designs are discussed over and over and revised. And this is not only done for the whole aircraft, ...


7

V1 is the speed at which you are committed to take-off, it doesn't mean you are off the ground. You can't retract the gear at V1 because you are still rolling on it heading down the runway. Vr is the speed at which you rotate the nose up to get into the air. Again you are still rolling down the runway with your nose in the air, you can't retract your wheels ...


1

That money is spent primarily on engineering, research and development, manufacturing, and flight test. Boeing employs nearly 60,000 people up at their plant in Everett alone, and these people are making at or in excess of $100,000 annually. Then there’s the cost of operating the buildings, the manufacturing and capital required to build the aircraft, cost ...


0

A lot is labor and indirect overhead burden costs (vacation time, sick time, state taxes, federal taxes, 401K matching, oversight of all that). Then engineering - someone has to enter all the thousands of pieces that go into an aircraft and engines. Model it. Create a simulator for it. Develop training for it. Line up business partners across the continent (...


1

Sometimes pilots are reluctant to declare emergency for different reasons( media, Inspection,..).even in a real emergency some pilots do not use related phraseology to convey the state of the flight. Controllers should be trained to resolve any confusion in communications resulted from several factors such as sociocultural and cognitive effects , in these ...


3

Note: You did not specify a country. I will answer for EASA. You don't need to obtain a PPL, you may use the MPL (Multi-Crew Pilot Licence) if you fulfill the requirements. From EASA Part-FCL (emphasis mine): FCL.405.A MPL — Privileges (a) The privileges of the holder of an MPL are to act as co-pilot in an aeroplane required to be operated with a ...


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