I recall reading several complaints that rof wind direction in FMB has the wind running opposite to its stated direction. An easterly wind is moving towards the east for example, instead of away from it.

I, also as "no pilot", would offer that the difference, again, is that your observations are with respect to the ground (or the water in your case).

While a plane might weathervane on the ground, it's because the wheels are on the ground, providing some friction and a pivot point. Your windsurfing board would behave very differently if it was 1000 ft. in the air, and you were able to keep it up there with magical anti-gravity. Without any contact with the water, and no motive force (thrust), you'd mostly just float along with the wind. The sail would not fill with air, and would not create lift.


BullPup's experiment, if I'm reading it correctly, seems to confirm my observations about the plane tending to roll into the wind, all other factors aside.

That about sums it up right there.

Just like a tethered blimp will weathervane into the wind, yet a free flying blimp can go where ever.


About the FAA books, yes there is some weird stuff in there, but it's mostly great info, specially when trying to explain to someone who has no clue.

I don't like the whole side slip versus forward slip. IF you look at their pictures they are the exact same picture but one of the pics is just rotated about 30degrees... It's just confusing for new students. I think that's why they are changing the side slip to the "wing low" for the xwinds, also makes sense since you land well wing low into the xwind.

I also hate how they teach forward slips... Always full rudder then just use enough aileron to keep lined up with the runway. There's not always a need for full rudder... I prefer just a slight slip the entire final approach. This effectively allows you to increase your current glide path if your engine quits by just relieving the slip. In some planes it allows for better visibility on final also. Just slip however much you need.

About them being slow to update info, well they are government and you know how efficient that is...

Yes I think it does, for the Albatross DVa at least, and I think it's confirmed now I've tried with no wind and found no such behaviour. I'll have to try with the rest of the aeroplanes (which, happily, I now have thanks to the recent sale!).

To be honest, it doesn't bother me unduly; I'm no pilot and it certainly doesn't detract from my enjoyment of the game. It does appear there's something a bit off though.

I have never noticed it, and I think why I havn't is because I'm never flying straight for very long in the sim. I don't much care for navigating from point A to B since I get plenty of that in my real life. My ROF time is usually spent dogfighting or flying through my obstacle course I built out of bridges, buildings, balloons and ships. I do all of the crazy stuff in ROF that I can't do in real life.

I'm a real pilot and this problem drives me crazy as it's just flat out wrong, even though I personally haven't noticed it. I'm willing to bet that it wasn't modeled this way intentionally. I bet it's just a bug that nobody really noticed.

I have now done a bit more testing all with the same settings as above and with all the aeroplanes except the rotary engined ones.

Aeroplanes tested - All Albatross models, Fokker DVII, both Pfalz, SE5a, Spad and Dolphin.

All the aircraft seem to be affected to varying degrees as follows. (Albatross and Pfalz seem worst, Spad and Dolphin - not much movement at all).

There definitely seems to be a tendency to bank left from a horizontal start when the wind is to the left. The aircaft then enter a slow left turn which they remain in. The only pilot input is elevators to keep the nose level with the horizon. I can't repeat my earlier observation of the DVa rolling back right and reversing the turn when the wind comes around that side so I think that was operator error!

The tendency to bank right from a horizontal start when the wind is from the right is much less.

Further testing with zero wind reveals the left banking behaviour is still there, but much less pronounced.

Summary -
Wind from left = pronounced left banking
Wind from right = minimal right banking - difficult to be conclusive
No Wind = minimal left banking

Conclusion -
I think there may be two elements at work. One, perhaps there is a very small counter-rotation with the propeller modelled which is pulling the aeroplanes into an almost unnoticable left bank. Two, a possible bug with the wind which excarcerbates the torque rotation when it is from the left, and cancels it out when it is from the right.

More Testing Required -
Bear in mind despite my best efforts there are a multitude of ways operator error could have influenced the tests. We need lots more people to try this out.

Anyone still reading?

EDIT - removed D2 from my list of aeroplanes tested.

I say yor'all nuts. Speed is measured by time and distance. There must be something to relate to measure by. It's all relative. If you moving 100 mph to have to measure that against some other object, be it earth or sun. If you want to you could throw in the speed of the rotation of the earth, the earth around the sun, the sun around the galaxy... But that is not useful info. The only useful info is the speed of the plane from a given fixed point on earth or in relation to another plane (closing speed). If in fact you are heading into a head wind and move backwards you might have a high rpm on your motor but it is still not traveling distance as fast and far as if you had the same rpm and no headwind. Gunloon I can tell is a smart guy but he ain't talk'n about what I'm talk'n about.

We only use the ground as a reference point because that is what we are used to since we are a ground based animal. Yes, you can measure speed from any point you wish and there are many many different speeds used in avaition. Speed in reference to the air is actually the most important as that is what keeps you flying.
Ground speed is important because it gets you to your desitination, but it doesn't keep you flying.

Headwind or no headwind you are traveling through the same distance of air if you are running the same rpm and airspeed, you just arn't traveling over the same distance of the ground because the volume of air you are moving in is also moving.

EXACTLY!

The trick, though, is knowing relative to what?

When your plane is in the air, the only thing that matters TO THE AIRPLANE is its motion relative to the air mass that surrounds it.

You could fly your Cessna at 70 mph into a 70 mph headwind. Your plane will remain perfectly stationary over a point on the ground, but it doesn't care. It just keeps buzzing merrily along, at 70 mph relative to the air. (Your passengers might care, though, especially if they have connecting flights at your destination.)

Indeed...BTW, did you look at the video link I posted? Much of the time the guy in the Camel was staying perfectly stationary over the ground in that stiff headwind, albeit with minor excursions in all directions (including backwards relative to the surface), and even though he screwed up the touchdown, he pretty much lowered the plane straight down like a helicopter (2:15 into the video). Fun watching.

Uriah, I'm lost. What am I talking about that you ain't?

[MF] Gunloon

I got it - Gunloon is talking about 'volume of air you are moving in' But I am talking about reference to the ground. Each have very different concerns.

Yes. And ground referenced speed is of no concern, as far as flying aircraft go.

That must be made absolutely clear, as enough people are confused on the subject already.

Movement relative to the ground is only interesting for navigation and when you are coming in to land (or to strafe, or to pick up a banner, or other such ground-interfaced activities).

We're all thinking of the Zen parables of the noiseless tree falling or the sound of one hand clapping

Just like a tethered blimp will weathervane into the wind, yet a free flying blimp can go where ever

Ah like a kite then when you need to let go of the string or the kite will zoom into the ground

The now freely-falling kite will turn in the wind like a weathervane though to present its smallest surface area to the wind? And the dihedral will be forcing the kite to face into the prevailing wind? You'd think. But now I'm not sure. Ah2 the kite will only do this is it is tethered maybe? And planes blow like leaves perhaps with the prop stopped

What about the force generated by the propellor being the equivalent of the force 'generated' by the held-string? We need diagrams

Ming

Spent some time trying to confirm this and it does seem to hold true. Also, check the angle of the exhaust when flying with a left crosswind vs. a right crosswind. It differs! I'm thinking we have quite a bug here.

The plane yaws do you mean Fred under a steady wind?

Is the force generated by the propellor acting as the string to the kite, a 'tethered' end, or can the forces generated by the prop be ignored as the whole caboodle is in the airstream

It's quite hard to do the thought experiment what with having normal and probably naive preconceptions of how things ought to work

The plane is pulling on the air mass I mean, there's the string-tug: or it could not be moving forward. Hmm it's pushing the airmass out the back though aaggh

I was smiling at reports of the antics of the earliest balloonists the other day, where they took oars into the gondola in case the wind dropped. Similar thing going on in this case maybe?

Ming

Assuming the exhaust smoke is behaving correctly, it appears the beta (sideslip) angle of the aircraft changes depending on whether there's a right or a left crosswind - without any rudder input to make it change. This also agrees with the rolling tendency.

Going to go back to it later tonight and check if the direction of roll coincided with the slip as indicated by the exhaust.

Nothing theoretically wrong with oars, they just happened to deliver far too little thrust. Santos-Dumont later put four oars on an axle, making a propeller, connected it to an engine and flew around the Eiffel Tower.

Is this reported on the official forum somewhere, or is someone from the developers reading this?

Still can't get to grips with the way the official forums are arranged, and searching shows nothing relevant.

Please can you write a brief engineering-type report on this possible-bug fr, here or in a PM and I'll make sure that VikS sees it. Han is on holiday I think and Jason will be busy on the Fourth

Still can't get to grips with the way the official forums are arranged

Sorry about that mate, down the line Jason may permit a revamp of the English forums with a more structured format better suited to the forums' English-as-first-language members requirements. He's got so much on his plate at the moment though that one dares not bother him, but yes that would be desirable

Ming

Unfortunately, he's right. You can test this with the autopilot on in a strong wind. Fly the four cardinal headings and note the slightly different stick positions in each. This may also explain the wacky stall behavior when flying on servers with strong wind/turbulence present.