Air 2 Would you fly your drone in this wind?

[Meta4]

Surely area presented to the wind will make a difference to how much a drone is affected.

The cross sectional area is already a factor into the drone's still air max speed

Though not sure why the Yuneec H520 did so well vs the P4 and Inspire, as . . .

Top speed from manufacturer specs.

H520 45mph
Inspire 49mph
P4 45mph

Can't be just speed.

But those speeds for the DJI drones are for sport mode.
If they were in P-GPS mode, they wouldn't have been able to use the max tilt angle and max speed.
The video doesn't give enough details to know what mode the drones were in.
The big difference between the Phantom and others needs explanation before the video can be accepted as a true test.

Perhaps the Yuneec has access to full tilt in any mode?

 

[MAvic_South_Oz]

The cross sectional area is already a factor into the drone's still air max speed

But those speeds for the DJI drones are for sport mode.
If they were in P-GPS mode, they wouldn't have been able to use the max tilt angle and max speed.
The video doesn't give enough details to know what mode the drones were in.
The big difference between the Phantom and others needs explanation before the video can be accepted as a true test.

Perhaps the Yuneec has access to full tilt in any mode?

Yeah good point, I suspect they all would / should have been in normal modes for a test like that.

 

[BigAl07]

Contrary to popular belief, the weight of the drone is not a factor.
The speed of the drone is what's important.
A drone that can punch through still air at 50 mph, could make (slow) progress against a 49 mph headwind regardless of its weight.

What? Weight of the aircraft absolutely IS a factor in this conversation. If you had two identical objects in the air except weight, the heavier will be more resistant to change in movement from the wind due to inertia. Just because the object is airborne doesn't mean it's weight doesn't come into play with it's inertia. While it's noted in many papers/posts etc that weight isn't a factor in an airplane's inertia only because they have simplified the description to keep motion/weight at a constant. Fact of the matter is weight of the aircraft does apply when talking about how easily the wind affects the aircraft in flight. A heavier aircraft (with all other factors being equal) will be less affected by wind.

 

[Meta4]

What? Weight of the aircraft absolutely IS a factor in this conversation. If you had two identical objects in the air except weight, the heavier will be more resistant to change in movement from the wind due to inertia. Just because the object is airborne doesn't mean it's weight doesn't come into play with it's inertia. While it's noted in many papers/posts etc that weight isn't a factor in an airplane's inertia only because they have simplified the description to keep motion/weight at a constant. Fact of the matter is weight of the aircraft does apply when talking about how easily the wind affects the aircraft in flight. A heavier aircraft (with all other factors being equal) will be less affected by wind.

That's a common misconception.
We're not talking about a stationary object being blown away.
We're talking about the speed that a powered aircraft is able to push through the air.
If you have two planes, the same size, but one is heavier and slower.
The faster and lighter one will be able to fight against the wind better.

 

[BigAl07]

That's a common misconception.
We're not talking about a stationary object being blown away.
We're talking about the speed that a powered aircraft is able to push through the air.
If you have two planes, the same size, but one is heavier and slower.
The faster and lighter one will be able to fight against the wind better.

You made a couple mistakes...
1) you are interjecting "slower" into the equation.... That's not part of the equation. In my post I clearly stated "two identical objects in the air except weight". If ALL things are equal except weight the heavier will be more resistant to sudden changes due to inertia.

2) We aren't talking about the aircraft merely being able to fly into the wind but the mass of the aircraft resisting the force of the wind such as in gusts. If the wind (force) were constant we could indeed discount inertia etc but we aren't talking about sustained/constant forward flight.

 

[Meta4]

You made a couple mistakes...
1) you are interjecting "slower" into the equation.... That's not part of the equation. In my post I clearly stated "two identical objects in the air except weight". If ALL things are equal except weight the heavier will be more resistant to sudden changes due to inertia.

2) We aren't talking about the aircraft merely being able to fly into the wind but the mass of the aircraft resisting the force of the wind such as in gusts. If the wind (force) were constant we could indeed discount inertia etc but we aren't talking about sustained/constant forward flight.

Usually when this is discussed, it's about smaller, slower drones and larger, heavier drones, rather than drones that are identical except their weight.

Perhaps @sar104 could comment on the physics involved?

 

[Deleted member 103366]

Would it smooth things out to say that weight/mass/inertia would smooth out the ground speed variations in gusty wind but not affect the speed in steady wind?
That ignores to some extent the component of the thrust needed to simply keep the drone in the air and consequently the associated pitch angles.

How do you do that 'at xyz' thing? I can't seem to get it to work.

 

[tlswift58]

I Agree. There was a group that did a test a few years back with a Yuneec Typhoon 520, a DJI Phantom 4 and an Inspire 1. Winds were above 35 with gusts to 50. Not as much as the OP showed but close enough to get an idea what it might look like. Some may find the results interesting.

Having "worked" in those kinds of winds at Nellis AFB - outside of Vegas - on the flightline - they are no joke. Esp in winter when the tumbleweeds get caught up in that and slam into you. That hurts!

Surprised the Yuneec did so well, but there is NO WAY JOSE I'd put an Air2 or even less chance a Mini into a sustained wind more than 20 - 25 mph. And def not at any altitude and expect to ever see my drone again. I have flown in some 15 - 20 mph winds and the Air2 does a good job staying fairly stabilized, yet the fight against the wind drains the battery in no time - so a flight may last maybe 10 minutes at best.

Anyone risking a flight at any altitude over about 50-75 feet in a wind 25-30 mph best have some good insurance - esp when flying any of the Mavic or smaller series drones. The Yuneec is a big heavy bird, so has a better chance. I'd thought the Inspire would have done better - being bigger / heavier than it did.

 

[Blume TMS]

It is obvious to me why the Yuneec H520 did better than the others.... 6 props have to give the thing more control and ultimately power against the wind than the standard 4.

 

[Droniac]

That's interesting, but it's only demonstrating ability to hold position (or not) while hovering.
That's different from ability to be flown in wind.

Drone speed is directly related to the tilt angle and the Phantom and Inspire have different tilt angles for P-GPS and Sport modes.
Available specs for the Inspire don't show what the top speed in P-GPS is.
Neither of those drones would be able to use Sport Mode tilt angle or speed if left hovering in P-GPS.
(Some recent Mavic models can use greater tilt angles in strong wind situations.)
If the Phantom's obstacle avoidance sensors were enabled, its tilt angle and speed is further reduced.

It's hard to get much information on the Yuneec to know if it can use its max tilt angle in any flight mode, but the max speed in the specs I looked at, is not much different from the Phantom in P-GPS mode.
H520 = 17 m/s .. Phantom = 16 m/s in P-GPS with OA disabled.

Found this very informative for me. Thanks for share. Point taken. Godspeed, Droniac

 

[Lets Fly]

The question was , "Would you fly your drone in this wind. No, would you?

 

[Reginald E Johnson]

No one? It just depends on the weight of the aircraft, available power to overcome the wind, parameters of the flight controller, and the skills of the pilot/operator. I would bet you $$ there are several who have battled winds like that (and more) with great success using the right equipment and the right skill set. Granted there are MANY who have battled winds much less and lost but that's also equipment/skills issues.

I once flew in conditions like that for about 5 minutes! My Mavic Pro was almost at a 45° Angle! Everyone was impressed with the Video!

 

[Reginald E Johnson]

So a few hours before this video I flew my drones at the coast, but within 2hrs the winds picked up so much I stopped after the wind blew my sunglasses off into the surf. My wind meter displayed 43mph avg with gusts over 60mph.

The Oregon Coast

 

[Dbez1]

In answer to your original question, there is no way I’d put an expensive drone up in those conditions.

 

[Meta4]

Would it smooth things out to say that weight/mass/inertia would smooth out the ground speed variations in gusty wind but not affect the speed in steady wind?
That ignores to some extent the component of the thrust needed to simply keep the drone in the air and consequently the associated pitch angles.

I doubt there is any significant affect due to the mass of the drone.
The issue is about a drone moving across or through a current of air that is moving .
A lot like rowing a boat across or into a strong current.

Air and water air both fluids.
Currents in water and in air (wind) act in similar ways.
A strong water current will carry a heavier boat downstream just as fast as a lighter boat.
How fast the motor can push the boat through water (or the drone through air) is what affects it's performance in a current or wind.

 

[Meta4]

It is obvious to me why the Yuneec H520 did better than the others.... 6 props have to give the thing more control and ultimately power against the wind than the standard 4.

More props only help if the drone can fly faster than the wind speed.
A drone with 12 props will still be blown backwards if the wind is faster than the drone can fly.

 

[Droniac]

The question was , "Would you fly your drone in this wind. No, would you?

No

 

[Droniac]

Risk v. Reward.

 

[sar104]

You made a couple mistakes...
1) you are interjecting "slower" into the equation.... That's not part of the equation. In my post I clearly stated "two identical objects in the air except weight". If ALL things are equal except weight the heavier will be more resistant to sudden changes due to inertia.

2) We aren't talking about the aircraft merely being able to fly into the wind but the mass of the aircraft resisting the force of the wind such as in gusts. If the wind (force) were constant we could indeed discount inertia etc but we aren't talking about sustained/constant forward flight.

Usually when this is discussed, it's about smaller, slower drones and larger, heavier drones, rather than drones that are identical except their weight.

Perhaps @sar104 could comment on the physics involved?

You guys are talking about different things.

First - recall the forces that act on a rotorcraft:

In hover or steady flight, neglecting aerodynamic lift due to the airframe, which is fairly small, the aircraft weight is balanced by the vertical component of motor thrust (labeled "lift" in the diagram above) and the aerodynamic drag is balanced by the horizontal component of the motor thrust ((labeled "thrust" in the diagram above).

In a steady wind field (which is the case that @Meta4 is referring to) the mass or weight of the aircraft has no effect on its ability to hold position or progress against the wind because no acceleration is involved - it's entirely governed by the maximum airspeed of the aircraft in steady flight.

In an unsteady wind field (@BigAl07's example) it's potentially much more complicated, since the response depends on the rate of change of the wind speed and direction relative to the rate at which the aircraft can change tilt.

If the aircraft can change tilt fast enough to keep the forces balanced then again - aircraft mass is not a factor and maximum airspeed is all that matters.

Mass comes into play if the changes in wind speed and direction are rapid enough that the thrust vector cannot change fast enough to follow them. In that case the forces on the aircraft will not be in equilibrium and the aircraft will be in unsteady flight. With some simplifying assumptions, the resulting deviation from steady flight becomes a function of rate of change of drag, maximum thrust/mass ratio (maximum available linear acceleration), maximum thrust/moment of inertia ratio (maximum rate of change of attitude) and maximum rate of change of thrust (maximum rate of change of acceleration).

 

[Meta4]

In a steady wind field (which is the case that @Meta4 is referring to) the mass or weight of the aircraft has no effect on its ability to hold position or progress against the wind because no acceleration is involved - it's entirely governed by the maximum airspeed of the aircraft in steady flight.

Thanks Sar ... so for most flight situations involving wind, the weight of the drone makes no difference and all that's important is how fast the drone can fly.