# Recent content by XXavier

1. ### Viral Aerosol Spread Simulation

That's the airport of Murcia (LEMI). After much discussion concerning the name, the matter is still undecided. In the Wikipedia English entry, there's not a word about Cierva... https://en.wikipedia.org/wiki/Regi%C3%B3n_de_Murcia_International_Airport The problem is that Juan de la Cierva did...
2. ### Viral Aerosol Spread Simulation

A good thing that... And the best news is that the SPD is pushing for a complete withdrawal of nuclear weapons from Germany. I hope that our government may soon do the same for those infernal weapons still stocked in US military bases in Spain... The world may be exposed to many risks, as the...
3. ### Power Question on Ultralight Gyros, including Chuck's UL

For 550 lbs, all other things being equal, you can find the power required by multiplying the figures of message #2 by 550/250...
4. ### Power Question on Ultralight Gyros, including Chuck's UL

A very rough estimation follows: Let's assume that your gyro has a best L/D of 5 at 25 m/s (56 mph). For a mass of 114 kg (250 lbs), the 'gravitational power' involved in that glide would be 114 x 9,8 x 25/5 = 5,6 kW. In order to fly s/l at 25 m/s you would need exactly that power. If you also...
5. ### Power needed to spin rotors

I understand the rationale of having negative pitch on the ground, so to 'press' the machine downwards, but ¿negative pitch for autorotation...? The usual, fixed positive pitch for gyros, that are in permanent autorotation, is about 3º. Can't see the reason why helicopters may be different in that..
6. ### Power needed to spin rotors

I don't understand the last statement: 'The most surprising result was that to spin the rotors while generating zero lift required 9kW, but to generate 190kg of lift required only an additional 7 to 8kW.' With the rotor turning, there is always some lift. Of course, if the lift is less than...
7. ### Viral Aerosol Spread Simulation

The danger is clear, I agree, but sooner or later, we are all going to get infected. Being alive has always risks... It is one thing to take precautions to avoid infection when caring for a sick person, but it is quite another to take those precautions in normal life. Wearing a mask and gloves...
8. ### Tire Pressure Monitor for gyro.

Very useful, thanks!
9. ### Almost life sized radio controlled "Little Nellie"

Some information found in the internet, on the model; It's interesting and instructing to try some simple calculations. The original 'Little Nellie' has a flight mass of 249 kg. Following the proportion law for volume (and mass, assuming the same global density) , the model mass should be 249...
10. ### Performance Calculation of Gyros

The horizontal component of the glide ratio, as calculated by GPS, is an 'absolute motion' with reference to the ground, and not to the mass of air you're flying in. That may be the reason for a difference, the glide ratio (with reference to the ground) being smaller with a headwind and larger...
11. ### Focke Achgelis Fa 330

The rotor is of the conventional, fully articulated type. The machine could have been built with a two-blade teetering rotor, much simpler and lighter, but that type of rotor either wasn't known to the designers, or perhaps not yet invented...
12. ### The good, the bad and the ugly (t/offs & landings video of one training session).

Not that bad... Most of those landings are, IMHO, more or less correct... Perhaps the speed is a bit high... I use (or used, before these troubled times) to fly a M24, and my landings are far worse...
13. ### Calidus vs Ela Eclipse 10 What is your opinion?

Interesting, thanks...
14. ### Calidus vs Ela Eclipse 10 What is your opinion?

That's surprising, and alarming too... More photographs and details of that hard landing (must have been really hard...) will be welcome. Concerning the mast thickness, I very much doubt that the manufacturer may have opted for such a radical 'solution' in order to lighten an structure. The...
15. ### President trump

I believe in freedom. I hope the moderator or moderators of this forum should not 'shut this stuff down'...