24

The absolute minimum for a generalized vehicle that needs to know its position and attitude (orientation) in space is one per degree of freedom. This can be reduced if we have information about the natural modes of the system and their stability. For simplicity, let's assume a vehicle moving in 3 dimensions, that means a total of 6 DoF: 3 coordinates in ...


22

Here's a photo: Retired Lt. Col. Thomas Mudge, a ground controller for the 82nd Aerial Targets Squadron, remotely pilots a QF-4 during a Combat Archer mission May 12, 2015 at Tyndall Air Force Base, Fla. QF-4s were retired in 2016. They are now flying the QF-16.


15

It's probably possible with only the GPS receiver, but it wouldn't be easy and you might have to make some compromises on the airframe design to achieve the necessary passive stability. The traditional set of sensors for this kind of application are, roughly in order of priority: GPS 3-axis rate gyro 3-axis accelerometer 3-axis magnetometer pitot alpha ...


10

Maybe wings never mattered... Altitude: The answer depends a bit on the design of the craft in terms of control surfaces/wings. Atmospheric reentry begins at the Karman line at an altitude of 100 km (62.14 mi / ~ 54 nautical mi) (327,360 feet) above the surface. Which is generally when air resistance starts to matter but that does not mean control surfaces ...


8

Aspect ratio. Look at your two images: both wings offer the same wingspan, but the former requires a lot more wing area for it. Wing area is weight. More wingspan for less wing area means better fuel efficiency and thus better range. Poor aspect ratio, leading to excess induced drag, is a major disadvantage of delta wings. Much of modern stealth design is ...


7

As I am closely working on some of these projects, I think I can answer. Let me start from: if the power fails this is a rather extreme situation, since everyone is including emergency functionality in case the batteries get below a charge guard level, triggering an emergency landing (still powered). So to have the "power fails" scenario that your ...


7

If you just want your UAV to fly to a waypoint, you could do it with a GPS sensor alone, if it was based on a very stable aircraft like a "Gentle Lady" or "Radian" r.c. sailplane, as long as you weren't flying it in very strong wind where there was the possibility of the aircraft going backwards over the ground when pointing into the wind and flying at trim ...


6

According to the Airbus press release: The MALE RPAS is the first unmanned aerial system designed for flight in non-segregated airspace and will be capable of performing a range of missions in intelligence, surveillance and reconnaissance, both wide area and in theatre. A twin-turboprop propulsion system will deliver energy for the mission system ...


6

GPS Barometric sensor occasionally recalibrated from the GPS Tach to maintain constant piston-engine RPM Gyro for roll stability These inputs sufficed for an autonomous chain-of-waypoints transatlantic flight sixteen years ago.


6

Perhaps a summary introduction in control theory could help you. From a control point of view, your aircraft is a dynamic system, which can be described by a state and a dynamic model. The state is simply a collection of variables of where the aircraft is in each point of time. For a full description, you would have the position and attitude in space, as ...


6

There seems to be some ongoing research into just that: There is an effort underway to develop a UAV version of the F-16. This would be based on the QF-16, the remotely controlled target version of the F-16. The air force is already in the process of converting 210 retired F-16s to QF-16s and it was noted that with a little extra work the QF-16 could be ...


5

I know those things as squirrel cage blowers. As the video says, they are a good choice if you want to move a moderate amount of air without exposing rotating blades. Impeller, by the way, was initially the word for a sort of airscrew that is moved by the flow. The small thingy in the nose of the Me-163 rocket interceptor was an impeller and needed for ...


5

This has a pretty broad range of answers for this, but I assume what you are asking is what a flight ready QF-16 would sell for should it become instantly available on the civilian market. Well the short answer is whatever someone is willing to pay for it. The long answer is that aircraft values are based on a large range of variable, including, but not ...


5

For a quadcopter, flying close underneath a flat surface will increase the amount of lift produced, but this will make it harder to control (unless the quadcopter is equipped with appropriate control software). According to comments by Alex and Peter Kämpf, if you fly a quadcopter close underneath a flat surface, the quadcopter will tend to get "sucked up" ...


5

Normally, controlled airspace ends at 60,000 ft (Flight Level 600). Airplanes flying higher than that would be operating outside of controlled airspace. Currently, there is no internationally agreed definition where national airspace ends. However, aircraft flying higher than 60,000 ft (18,288 m) could claim to fly outside of national boundaries. There are ...


4

As a drone hobbyist, is flying below the listed FAA UAS ceiling a violation of controlled airspace? Short answer: As of now, since the LAANC pre-authorization system is not yet up and running for recreational SUA flyers, any recreational sUAS operation below 9000' MSL in the lower left corner of the grid square highlighted in the question would be ...


4

......the same way you decelerate any other kind of aircraft. Once released from the Mothership at idle power, it slows down until reaching an appropriate cruise speed thence power is increased to maintain speed. If the release speed of too high for the UAV, one might use some kind of a frangible capsule equipped with a drag chute or other high drag device ...


4

Some UAVs carry VHF or UHF airband radios to communicate with air traffic control and other aircraft. The voice channel is relayed to and from the remote pilot operator via satellite or another form of datalink. I've heard UAVs taking with Joshua Approach in the Mojave Desert, and one time Joshua called one out to me as traffic and vice versa. I agreed to ...


4

Depending on who you ask, outer Space starts between 80 and 150 km, whereas 100 km is the most common defintion (Kármán line). Countries do not acknowledge the transition from airspace to outer Space as territorial boundaries. Instead the function of an object is used for distinction: if it flies, it must be an aircraft and subject to national ...


4

Laws around drone use are very new, and the only way to be certain about this is to have a case come to trial. You probably don't want to be the person it comes to trial over. A lawyer would give you a much better interpretation, but even they can't be sure. If you are interested in my personal uninformed opinion (IANAL) then I think it would not count as ...


3

You can just let drag take care of it. Granted this means that you need to have the drone sturdy enough to handle that headwind. Too high speed is only a real problem when you go to maneuver the drone. Straight and level flight and gently adjustments is less of a problem. The next option is to launch upwards in a climb and wait until the drone has bled ...


3

One way might be to design the UAV to be deployed with flight control surfaces folded, use a parachute to decelerate, unfold the flight control surfaces at a safe speed and release the parachute. Another would be to deploy the UAV inside some sort of canister that only falls away at a safe airspeed, letting the drone then fly away.


3

Centrifugal stress on the disk is indeed the most pressing issue. Real life centrifugal compressors can get to a compression ration of about 4.2 for a simple single stage fan, at disk tip speeds of 450 m/s which is the maximum for high tensile steel. Exit speed at the disk tip is often supersonic and needs to be reduced to about 100 m/s, resulting in the ...


3

I'm not sure about everywhere but in the U.S. there is an app called "Airmap" Link to webpage. It's built for commercial drone operators but it can also be used by people flying for fun. There is a flight plan portion of the app that allows you to file for a flight. You specify time of takeoff, radius you'll fly in, altitude and aircraft. This is then ...


3

The Superintendent's Compendium for Gateway Arch National Park says Launching, landing, or operating an unmanned aircraft (UA) from or on lands and waters administered by the National Park Service within the boundaries of the Jefferson National Expansion Memorial is prohibited except as approved in writing by the superintendent. ...


3

MIT has produces a small-scale RC plane that's powered by ionic thrusters. These are not the same as ion thrusters in space; instead the ions here are created from the surrounding air. The benefit is that the plane doesn't need to carry its propellant. Since there are no fast-moving mechanical parts, this is very silent. I could even see this being used to ...


3

The class D airspace you are referring to is a control zone (CTR). According to article 24 of Regulation for Remotely Piloted Aerial Vehicles, the following applies to VLOS operations (emphasis mine): Except as required by point 6 below, RPAS operations shall not be conducted: a) within ATZ and beneath take-off and landing paths or at a ...


3

The ArduPilot project has probably already done a lot of the work for you, if you're more interested in the end result than in the process of creating it for yourself. Even if you choose not to use their software, there's probably good information regarding which sensors and how many are necessary. The APM:Plane subproject Supported controller hardware A ...


3

You want to move a heavy payload at low speeds. This means that induced drag will dominate the aircraft. If we assume a quadratic polar, the least amount of energy for staying airborne is needed when induced drag is three times higher than friction drag. Assuming a quadratic polar, the optimum lift coefficient at that point is $$c_L=\sqrt{3\cdot c_{D0}\cdot\...


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