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119

EDIT Huge apologies to one and all, in my first version of this answer I mistyped 184 as 84, and then proceeded to do all my calculations based on that. This is the corrected version. Also, huge thanks for all the up-votes and comments. I'm so glad it's not just me that is enjoying this question immensely. The radius of the ball in the image is 21 pixels....


58

Both have their respective uses. A fixed-wing carries far more water (3,200 gallons or 12 tons for the Be-200 vs 100-700 gallons for helicopters), but takes more local infrastructure to operate, and is more difficult to discharge exactly where you want it. A helicopter is more precise, but carries less water. A heli is quicker to load up and discharge near ...


51

The helicopter would be a UH60 Blackhawk. Max payload on a hook is 9000lb. At your mild steel density this is half a cubic meter, so the picture as you describe is impossible.


48

Of course the photo is absolutely real. I know a guy who knows a guy who says he met the guy in front! 3) Assume the wrecking ball is solid mild steel with a density of 7.85 g/cm3. That's where you went wrong. The angle of the line and the drag equation allow us to determine the ball's mass, given a known velocity. The ball presents a frontal area of 11....


19

Indeed helicopter/wrecking ball combo exists and do some useful job, check this video. The film shows how the Norwegian Public Road Administration cleared a potential rockfall debris prior to establishing an additional rockfall barrier fence. First they smash the cliff with a wrecking ball, then drop water over the same area using a water bucket.


13

Due to center of gravity limitations, it would be impossible for any type of aircraft to be loaded so that the front became the heaviest part. The aircraft would not be able to fly. These UAVs are meant to crash land and DO land on the front propellor. You can do a Google search and see multiple videos showing the “break apart” landings they are designed to ...


12

For something like a movable camera in a gimbal, or even a gyroscopic attitude indicator, it means that it is physically locked into place so that it can't move. On the gimbals (such as the camera pod in a predator, or other ISR asset) that can mean the camera is rotated into a stowed position, and then a pin is mechanically moved into place to keep the ...


10

I'm trying to drop a payload via parachute with some accuracy. Cut a hole in the middle of the parachute, make its edge smooth and install a pipe through the center of the box that contains the payload. Run the line through the pipe and parachute and let the payload fall from the balloon. I believe the trick will work for small parachutes able to deliver up ...


10

This would be an uncommon situation and the decision on what to do will typically be handled by your dispatcher. Take the extra gas and restrict passenger/cargo weight as necessary. This is the easy option but it could mean leaving people behind. Defuel to the normal amount of fuel needed (e.g. release + taxi + contingency fuel) This normally means the ...


9

It depends on what you are trying to do. The planes aren't doing direct attacks. In other words, they don't usually drop on fires. They lay down lines of fire retardant or water as a fire break. The fire burns up to the line, slows or stops, and ground crews can go in and stamp out hot spots. The big Erickson helis can also carry retardant or water and ...


8

This video on YouTube apparently shows that it has been done at least once. A rigid beam was used to counter the forces that would draw the two helicopters together. Screen grab: I also found this fascinating report (.PDF link) from Piasecki (now part of Boeing Defense, Space & Security) that studied the feasibility of attaching two CH-53D helicopters ...


6

It is going to vary according to flight mission, passenger count, season, or what part of the world the flight takes place. Here are the capacities from a company document. MD88/90 47USG (177.9L) MD11 250USG (946.4L) Estimated 732/733 40USG (151.2L) 737 60USG (226.8L) 747 3x 110USG = 330USG 757 66USG (249.8L)-Fill valve closes automatically at 50USG (189....


6

Centre of pressure (CP), by definition, is the point at which the aerodynamic moment of something is zero. If you are talking about the CP of the whole airplane, then at trim condition, the CG must always coincide with its CP. Period. This is achieved for any operational speed through well designed pitch control that varies in flight. For example, ...


5

If the ball is empty inside, it can probably be made even larger than the helicopter. ZMC-2 was a balloon made of metal, light enough to fly on its own. It even has some rudders that resemble the spikes of the pictured ball. It is probably possible to adjust the lift of the balloon slightly below its weight, so that a helicopter could "lift" it up. ZMC-2 ...


5

There are two different Maximum Take Off Masses (MTOM) listed in the graph: 73.5 T and 78 T. This is only a small selection. The Airbus A320 has many variations due to modifications to fuel tanks, fuselage, engines, wings and landing gear. The following MTOMs have been certified (EASA PDF): 66 T, 67 T, 68 T, 70 T, 71.5 T, 73.5 T, 75.5 T, 77 T and 78 T. In ...


4

Normally I would put this as a comment since I retired in 1999, and I don't know what current practice is. However, this is a bit too long for a comment. Also, this is from memory and it's been a long time now, as it's from my experience with load sheet preparation in the late 1980s and the 1990s. If a more recent useful answer appears, I'll simply delete ...


4

Yes, this is possible, as demonstrated in this video from almost 2 years ago: Video Each helicopter probably does not weigh more than the woman being lifted. The two helicopters are tilted such that the forces are in equilibrium with no collisions. Both are coordinated as two pilots are flying these by Line-of-Sight.


4

In theory, with that load, the rotor revs will be higher during the descent, and releasing the load just before flaring will give the pilot more rotor energy to control the aircraft with the collective in the last stage of the landing. But it would be more prudent, in my opinion, to release the load as soon as possible. After all, in any dead stick landing, ...


4

Source: Popular Mechanics The Antonov-225 currently holds a number of records... Heaviest maximum take-off weight at 710 tons (1.4 million pounds) Total air lifted payload of 558,590 pounds Single item payload of 418,830 pounds Longest wingspan of 290 feet for any aircraft in service (Stratolaunch and H-4 Hercules had larger wingspans, but neither are ...


4

Because: If centres of pressure and of gravity would coincide, there would be no inbuilt tendency for the nose to drop upon an adverse aerodynamic event like a stall. If someone walks along the aeroplane and shifts the CoG, the two centres no longer coincide. There is some range required for the CoG. An aeroplane must have static and dynamic stability in ...


4

Mechanically this can be done using the simplest form of pantograph, as a hinged parallelogram with one end fixed to the fuselage and the other to the ordnance pylon. Or, I suppose you could implement a digital one.


4

This is a complicated question, here is a simplified answer. Generating lift requires setting in motion a large quantity of air, as downwash. More lift requires more downwash, and that requires setting in motion a larger quantity of air- which requires more horsepower applied to the main rotor shaft. Note however that the rotor blades are designed to ...


3

Aircraft are not certified for one particular runway distance. They are certified to an absolute max structural takeoff weight, for airborne performance or engine out obstacle clearance. Performance charts will dictate the runway length required for any given takeoff weight and given weather conditions. If the runway is too short for that weight then the ...


3

Generally an aircraft will be certified for a range of runway distances based on headwind/air temp/weight, a correction chart will be provided in the POH allowing you to compute the runway distance for various conditions. For example here is the chart for the PA-28-161 I trained on The big planes have similar charts, you can find the 737-800 numbers here ...


3

These guys seem to offer some products in that space however it seems many of them are of the remote control variant (not fully automated). Crop dusting is a pretty routine task and you could easily program a drone to cover a specific field at a given time and let it do its thing. The main issue you will face in the current market is simply useful load. ...


3

I once worked in the UAV company, which was contracted to supply a system to identify trees. To achieve this, all you need is a good camera and an image recognition software (now to be easily written using .NET). I have not heard about drones carrying such large amounts of chemicals, so sorry about that. In this part of the world (eastern Europe) we have ...


3

Zoom climb of the carrier is useless. The rocket can do it alone after release with the same effect and is slightly more aerodynamic as it does not have the large wings of the carrier. The rocket starts with certain amount of energy upon release. Part of this energy is kinetic, given by speed of the carrier, and part of this energy is potential, given by ...


3

If the fuel flow rate and the true airspeed are for the same polar point, the answer is easy. You cannot, however, determine if this is your maximum range because you do not know any other points of the polar. Your fuel consumption is MTOW - MLW. The flow rate will give you the flight time when you divide the fuel by the flow rate. With the flight time you ...


3

If the hot air balloon is well anchored you can probably just use your original plan. The winds aloft will push the balloon in the direction the wind is going, so the anchor rope should be at an angle relative to the ground. When you drop the parachute, those same winds should keep the parachute/payload pushed clear of the anchor rope. So long as the drag ...


3

The only real answer we can give to this is it depends It depends on the airline, the nature of the legs (long/short), the specific airports/countries involved (re-fuelling costs can vary significantly) and route profiles used. If the aircraft is doing 4 very short legs, the cost of carrying the fuel may be less than the cost of refuelling three times. ...


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