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 ...
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 ...
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 ...
7
votes
Accepted
How to estimate the ribs spacing?
All of the above. Mostly it's to achieve conformity to the "mold line", the outer airfoil contour, for as much of the wing as possible, and for buckling resistance of the flattened tube ...
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 ...
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 ...
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 ...
5
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 ...
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 ...
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 ...
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 ...
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, ...
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 ...
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,...
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 ...
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 ...
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 ...
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.
1
vote
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 ...
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
...
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 ...
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$^1$. ...
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 ...
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 ...
Only top scored, non community-wiki answers of a minimum length are eligible
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