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1 vote

Aircraft pitch and AOA change during a coordinated turn maneuver

Let us say I am flying a constant airspeed turn while maintaining my altitude, when I enter into the turn, lift has to be increased and since airspeed remains constant, the AOA has to be increased to ...
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3 votes

How are the landing lights of the legacy F-18 Hornet seen before landing on the carrier?

The colored approach lights that the LSOs reference are not unique to the legacy Hornet, every carrier based aircraft is similarly equipped. These lights come on as soon as the gear is down and ...
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7 votes

How are the landing lights of the legacy F-18 Hornet seen before landing on the carrier?

No. The lights match the standard AoA indexer in the cockpit. When the airplane is on AoA, the center amber light is illuminated, as is the amber ‘donut’ on the AoA display. If the airplane is at a ...
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2 votes
Accepted

What methods are used to calculate the geometry needed to obtain a bell-shaped lift distribution?

For an unswept wing of an at least moderate aspect ratio in subsonic flow you can use the Multhopp panel tabulation. This divides the wing into an odd number of sections and is easily implemented on a ...
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0 votes

What methods are used to calculate the geometry needed to obtain a bell-shaped lift distribution?

I think you are referring to a bell-shaped lift distribution for the entire aircraft. If you take a look at the SU-27 fight jet, you can see that the wings aren't distinct from the center body of the ...
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3 votes

Aircraft pitch and AOA change during a coordinated turn maneuver

Does the pitch angle remain the same as the pitch before entering the turn? Is the equation Pitch = AOA + FPA (FPA is zeroed in this case, I think) still applicable during this turn maneuver? No, ...
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2 votes

What is the purpose of the small vertical dorsal fin about halfway along the fuselage of the Boeing 737?

It's the antenna for the Left VHF communications radio - the ones for the Centre and Right radios can be seen under the fuselage.
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0 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

Option one is a fully closed system so its center of gravity will not (in steady state) be affected of the internal fans and wings Since all flow is inward bound in option two it would either go to ...
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1 vote

What does deploying landing flaps do to the (L/D)max and minimum drag speed of an airplane?

I thought that deploying flaps will increase both the drag and lift, thus increasing L/D ratio The lift coefficient increases, but the lift force does not, at least over the long run. The lift force ...
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1 vote

What does deploying landing flaps do to the (L/D)max and minimum drag speed of an airplane?

Lowering flaps generally reduces L/D max and reduces L/D max speed It really depends how you want to design your plane, but usually you want to have maximum excess power at your climbing speed$^1$. ...
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0 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

Expanding on @pilothead's answer, remember that the airfoil generates lift by creating a low pressure area above the wing. This low pressure area isn't just lifting the wing up, it is pulling in air ...
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  • 101
0 votes

Why are conventional gear planes designed with the nose pointing up?

Note that it is possible to design the AoA of a wing on a tricycle-gear plane in such a way that when you hit the right airspeed, the plane lifts off and flies itself off the ground, after which it ...
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0 votes

Why are conventional gear planes designed with the nose pointing up?

Principally conventional landing gear was used in the past for simplicity, lighter weight and propeller clearance. It still remains a popular configuration for aerobatic aircraft, ultralights, and ...
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4 votes

Why are conventional gear planes designed with the nose pointing up?

Tricycle gear airplanes typically "rotate" for takeoff-- the nosewheel is lifted off the ground to place the aircraft in a nose-high pitch attitude, to increase the angle-of-attack of the ...
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2 votes

Aircraft pitch and AOA change during a coordinated turn maneuver

Pitch attitude will be increased slightly as one rolls into a bank to increase the AoA in order to maintain a vertical component of lift equal to the weight of the aircraft. In addition power or ...
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0 votes

Aircraft pitch and AOA change during a coordinated turn maneuver

Pic source Aircraft pitch motion is defined relative to the aircraft: when it rolls, the pitch axis rolls with it. And seen from the plane, pitch angle is still Angle of Attack plus Flight Path Angle -...
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1 vote

Aircraft pitch and AOA change during a coordinated turn maneuver

Let's say you are in level constant speed linear flight where AoA = Pitch to the horizon. Roll to 45 degrees and vertical lift is now cosine bank angle × lift = .707 × Lift. Pitch (to the horizon) is ...
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2 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

In short, no. A aerofoil works by creating a region of high pressure below the wing and low pressure above, this provides lift. In the enclosed system, we still have high pressure below and low ...
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0 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

Sure, depending how you define "Lift" Option 1, no way. You could possibly make it leap into the air by sloshing the air around violently enough, but that's unlikely, unsustainable, and too ...
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4 votes

Why do so many UAVS use a V-tail configuration?

As you stated, V-tail has some advantages and some disadvantages when compared to conventional tail assembly. In case of UAVs the disadvantages are negligible, leading to them being a relatively ...
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0 votes

Aircraft pitch and AOA change during a coordinated turn maneuver

If you want to maintain 2Gs, your bank angle must be 60 degrees. And your a/c will be needed more lift to maintain altitude. So the only way to produce more lift without changing config’ is pulling up ...
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0 votes

Why would an airplane with fixed-pitch propeller(s) and no supercharging have manifold pressure gauges? (E.g. Ford Trimotor)

Everything I'm about to write is pure speculation, as I have no expertise in aviation and more specifically the Ford Trimotor, other than having visited the KingsfordSmith museum at Brisbane airport a ...
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5 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

You need to first understand what is lift in this situation. In all 3 diagrams. Lift is the force between the airfoil and the enclosed space. The lift will generate a force that pulls the airfoil ...
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5 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

Another way to get to the correct answer of "no" is that all your designs have wing sections in a tube. Any low pressure created on the upper surface of these sections is replicated on the ...
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22 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

Consider Newton’s third law - for any action there is an equal and opposite reaction. If the action is to lift the enclosure then what is the reaction? It has to be pushing against something. You ...
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8 votes

Can an encapsulated airfoil generate enough lift to lift the capsule?

Can an airfoil generate enough lift, if it is contained in an enclosed space, to lift the enclosed space? If this were possible, the enclosed structure would rise up through the atmosphere without ...
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  • 17.2k
2 votes

Why would an airplane with fixed-pitch propeller(s) and no supercharging have manifold pressure gauges? (E.g. Ford Trimotor)

The MP gauge will tell you at a glance if your carb is icing up, by reading greater suction in the manifold at constant throttle setting- telling you that something other than the throttle was ...
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5 votes
Accepted

Why would an airplane with fixed-pitch propeller(s) and no supercharging have manifold pressure gauges? (E.g. Ford Trimotor)

The MP gauges would be in the cockpit because they are referred to frequently and it's easy to install them remotely with just a hose connecting them to the engines. Gauges mounted on the nacelles ...
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2 votes

Why would an airplane with fixed-pitch propeller(s) and no supercharging have manifold pressure gauges? (E.g. Ford Trimotor)

RPM tells how fast the engine is turning, manifold pressure (indirectly) how much power it's producing. If you're in a steep climb, for instance, RPM will drop a little due to loading of the propeller,...
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1 vote

Has there ever been a VTOL aircraft thruster that generated lift through the use of a drag force?

Momentum is conserved, which means if something goes up, something else has to go down. That's just the way it is, unless you've invented new laws of physics, which I don't think you're claiming to ...
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5 votes
Accepted

Has there ever been a VTOL aircraft thruster that generated lift through the use of a drag force?

No, there haven't been any VTOL aircraft that used a device like that. There's a very good reason for this: this device will produce very little, if any, lift. If exactly 50% of the air exits out of ...
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-1 votes

How does the pressure change in the Air Cycle Machine?

The expansion turbine removes ALOT of heat from the airstream converting it to work turning the turbine which turns the compressor. This accounts for both a pressure drop & a temperature drop
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10 votes

Why does the hardpoint mechanism on sweep wings produce a contact trace in front of the axis?

Having put on probably hundreds of pivot pylons on an F-111E back in the late '70's, the pylon is NOT attached to the skin. There is one large attachment collar. Teeth on the pylon meshes with teeth ...
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