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# Tag Info

24

Horsepower cannot be converted into thrust without knowing the speed at which this is done. In your case this is zero, so the special equation for static thrust applies. With $T$ for thrust, $P$ for power, $\rho$ for air density and $d_P$ and $\eta_P$ the propeller diameter and efficiency, respectively, this is T_0 = \sqrt[\LARGE{3\:}]{P^2\cdot\eta_{P}^2\...

22

No, flaps are never used during a nose dive. We need to distinguish between two scenarios: Intentional nose dive: this is actually called a rapid descent maneuver. The FCTM (Flight Crew Training Manual) has a whole section dedicated to it. The general procedure looks like this: From the Boeing 737 NG FCTM (7.5 Maneuvers - Rapid Descent - Level Change (LVL ...

12

Complicated is a matter of opinion and I wont address that specifically since its somewhat subjective. But the core of the question is "why did the L-1049E have 3 tails" which is a legitimate question for this site. The design was to allow the aircraft to fit in hangars of the time A sleek fuselage, something like an elongated fish with smooth curves, ...

11

Firstly, it does not control the pitch of the helicopter, that can be achieved using the cyclic control. Secondly, it is named collective because it changes the pitch of of all the main rotor blades collectively, as in, at the same time and by the same amount. This is different from the cyclic control which adjusts the pitch of the blades as a function of ...

6

"Collective" is short for "Collective Pitch Control", which, you know, controls the pitch of the blades collectively. It's on the left side because the really fine motor control required of flying a helicopter with the cyclic is best suited to the right hand, and 90% of the population is right handed. A lot of machines (Hughes and others are exceptions) ...

5

As Ron points out in the comments the question is not so much where as it is when. Aircrafts see the density altitude of the air around it not the true altitude they are at. On a very hot day at a very high altitude airport the density altitude may very well be higher than the true altitude by a significant amount which affects takeoff performance. The FAA ...

5

Because even with constant power, thrust decreases with velocity, also known as TAS. Drag depends mainly on the dynamic pressure, which is what IAS represents, so if you had the same thrust, you'd have the same IAS too. However a piston engine produces approximately constant power (if your RPM is in the optimal range), and power is thrust times velocity. ...

4

You can find the full POH here, no wind, standard atmosphere, at gross weight you are looking at 3800 ft. of ground roll and 4700 ft to clear a 50 foot obstacle. Take a look at the charts for the other weights as well as other runway surface types. (source)

4

The short answer is: because not all of the incoming air can fit under the airfoil, so some of it gets pushed up and above the leading edge. This air could also fit under the airfoil by other means like becoming denser (compressing), but that requires more energy, so it mostly flows around. In your image, the effect is exaggerated by the closeness of the ...

4

The second segment of the takeoff is defined as (source: skybrary.aero): Second Segment - begins when the landing gear is fully retracted. Engines are at takeoff thrust and the flaps/slats are in the takeoff configuration. This segment ends at the higher of 400' or specified acceleration altitude. In most cases, the second segment is the performance ...

3

There are several considerations for flying polar routes, but no special modifications are necessarily needed. Navigation is different, as Lat/Lon (specifically longitude) converge to become meaningless close to poles, so aircraft traditionally use a grid navigation system. Aircrew should also be aware of the difference between magnetic and true north, as ...

3

No they are different. Gliding for endurance, maximum time in the air, is at minimum sink rate, which is usually close to stall because it's where maximum lift is being generated. In a glider this is the speed you thermal at. In a power plane it might be the speed you'd glide at if you wanted to delay the inevitable as long as possible for some reason, say ...

3

Both the cyclic and the collective change the pitch angle of the main rotor blades. The cyclic is typically located in front of the pilot and is controlled with the right hand (presumably because most people are right handed), while the collective is controlled with the left hand. (image from Wikimedia, from Helicopter flight controls) The pitch angle of ...

3

Looking at the Performance Limitations of the Boeing 737 (page 3), we see that the Flap Limit Speeds are +================+==============+ | Flap Position | Limit Speed | | | (KIAS) | +================+==============+ | 1 | 250 | +----------------+--------------+ | 2 | 250 | +--------------...

2

Lighting the afterburner will only cause a pitch change and AOA change if the thrust line of the engines does not pass though the Center of Mass of the aircraft. If the thrust line pases above the center mass, increasing thrust will cause a nose-down pitch change, if the thrust line is below the center mass it will cause a nose up pitch change. But, more ...

1

Simple answer: The plane that divides the air that goes below the airfoil from the air that goes above sits quite a bit below the leading edge. There are several things to see here: Local speed: The closer and more focused the smoke lines are, the higher the local flow speed. Local pressure: Speed equals lower pressure, so the area of the closely packed ...

1

Both are wrong. (Or rather, both are partly right, which makes them fundamentally wrong). Precession happens when there is an 'input' rotation (moment) and not by itself. When you balance the airplane to fly straight and level, there is no gyroscopic moment. The gyroscopic moment is perpendicular to the external rotation, so it can be directed anywhere ...

1

Generally you won't find published POH documents for plans built homebuilts, as each aircraft is unique, the individual builder being the "manufacturer". Possibly, a builder has made his own POH. Best bet is to write to the guy currently marketing the plans and selling parts, Creighton King.

1

You've made quite a lot of mistakes in your math, some less severe and some more severe; you may want to think about these. Notation mistakes These mistakes are not so severe; we can still tell what you're talking about. The unit of energy you're talking about is called the "foot pound" or the "foot-pound," not the "foot/pound." A foot pound is a foot ...

1

The manufacturer lists over half a dozen variants of Hunter two-seaters. You probably mean the T.7. For a fair comparison, its closest single seat variant is the F.6, maximum speed Mach 0.94 (715 mph) at sea level. The T.7A, a T.7 with different instruments, has a maximum speed of Mach 0.92 (690 mph) at 36,000 ft. So the T.7 is a few per cent slower than ...

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