Translational lift begins flying, hovering is what you need to photograph.

[Dragonflyerthom]

TBE, drifting, and hovering are term thrown around here like salt and pepper. These can effect your filming but they are not flying. Until you go into translational lift you are just playing around with some of effects of a hovercraft. You need to learn how to fly this craft then you will get better. This will improve your ability to control the TH, and if you like to take stills and videos it will get better also. The ST16 will become second nature. You want to be at this level. It and you will become one. Hey I'm still learning myself. Fly safe.

 

[BoostedPerspective]

Translational lift?

 

[OnTheRopes]

Translational lift?

Translational lift - Wikipedia, the free encyclopedia

 

[Dragonflyerthom]

BP are you a pilot? The translation occurs when you go from hover to forward flight. This seem to be a function most don't get into. Thanks Steve. Guys I'm here to help. Look at this site as an on line ground school.

 

[BoostedPerspective]

This wouldn't be called "transitional" lift?

Just saw the wiki link. Disregard.

 

[Dragonflyerthom]

BP one (transition) is the act, the other(translation) is the effect. If you watch TH you will see the craft is tilted at several degrees in its forward flight. The gyro and GPS try to keep TH as level as it can in forward flight. I hope this is clear. Fly safe my friend.

 

[BoostedPerspective]

BP one (transition) is the act, the other(translation) is the effect. I hope this is clear. Fly safe my friend.

It is clear now, after reading the Wiki. Also went and looked into the effect in relation to quad/hex flyers as opposed to heli. Very interesting, and makes perfect sense.

 

[Rotorman]

ETL or effective translational lift will not occur on a hex or quad because these blades are not airfoils. They are propellers. The generate lift only through relative wind and down wash. They don't generate lift due to Bernoulli's principle so there is no rotor vortex to clean up. A helicopter rotor in hover only uses about 80% of its lift area because the tips have large vortexes trying to balance the pressure difference from below and above the rotor. When you move forward past 15kts the forward wind pushes the vortices off the rotor causing the nose to rise and less power demand due to effectively cleaning the rotor disk. This phenomena does not apply to drones because they simply only thrust and do not have the transverse flow of a normal rotor disc.


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[DerStig]

ETL or effective translational lift will not occur on a hex or quad because these blades are not airfoils. They are propellers. The generate lift only through relative wind and down wash. They don't generate lift due to Bernoulli's principle so there is no rotor vortex to clean up. A helicopter rotor in hover only uses about 80% of its lift area because the tips have large vortexes trying to balance the pressure difference from below and above the rotor. When you move forward past 15kts the forward wind pushes the vortices off the rotor causing the nose to rise and less power demand due to effectively cleaning the rotor disk. This phenomena does not apply to drones because they simply only thrust and do not have the transverse flow of a normal rotor disc.

You sure about that? Props are airfoils and they create lift which from a prop is called thrust. If they didn't create a vortex you wouldn't get ring vortex's in high humidity/High thrust conditions Here's a video showing that.

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and here's a NASA paper explaining how Props work

Propeller Thrust

I could be wrong I only have a CPL-MEI

 

[Rotorman]

Yes propellers have a small vortex. And yes some larger propellers are airfoils but the small plastic ones we use are not. The discussion was can you have translational lift on a quad or hex. In your video relative wind is perpendicular to the prop also. Translational lift is parallel to it.


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[DerStig]

Yes propellers have a small vortex. And yes some larger propellers are airfoils but the small plastic ones we use are not. The discussion was can you have translational lift on a quad or hex. In your video relative wind is perpendicular to the prop also. Translational lift is parallel to it.

Ummm that's all incorrect, plus I could point out symmetric airfoils and the fact that they have tip vortices. Vortices are caused by pressure differentials. The pitch of the prop causes the pressure differential. Yes you can have translational lift in a quad or a hex just like you can have settling with power (Vortex Ring State, is cause the loss off an Osprey) both are about relative wind

 

[Rotorman]

I disagree and as a helicopter pilot and CFI these are not airfoils. And no one was discussing settling with power. Quads are VERY susceptible to SWP.


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[DerStig]

I disagree and as a helicopter pilot and CFI these are not airfoils. And no one was discussing settling with power. Quads are VERY susceptible to SWP.

Well you're wrong, very wrong and I wonder how good of an instructor you are. These are airfoils but hey you're a "helicopter pilot and CFI" (FYI all I needed to get my helicopter ticket was to take the ride with the check airman but when my instructor was killed I wasn't interested in the check ride)

You might not want to look at this photo, it's gonna leave a mark....

That's an airfoil and it has a higher angle of attack at the root and washes out at the tip, Just like any other propeller and that happens to be one of the Props for an H

 

[PatR]

ETL or effective translational lift will not occur on a hex or quad because these blades are not airfoils. They are propellers. The generate lift only through relative wind and down wash. They don't generate lift due to Bernoulli's principle so there is no rotor vortex to clean up. A helicopter rotor in hover only uses about 80% of its lift area because the tips have large vortexes trying to balance the pressure difference from below and above the rotor. When you move forward past 15kts the forward wind pushes the vortices off the rotor causing the nose to rise and less power demand due to effectively cleaning the rotor disk. This phenomena does not apply to drones because they simply only thrust and do not have the transverse flow of a normal rotor disc.


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I disagree and as a helicopter pilot and CFI these are not airfoils. And no one was discussing settling with power. Quads are VERY susceptible to SWP.


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If you're an instructor you need to consult a dictionary and go back to school for a refresher in aerodynamics. Your students must be suffering terribly through your lack of knowledge. Propellers on quads and hexes are indeed airfoils, just as much as those found on RC aircraft and fixed or adjustable pitch full scale aircraft. A flat stick spun at high RPM and zero AoA generates very little or no thrust, and thrust is a function of lift derived from the shape of an airfoil along with AoA. Just because our propellers lack collective pitch does not mean they are not airfoils. They are just as much an airfoil as those found on the wing design of an airplane, but typically much more complex because of constantly changing pitch and chord thickness and blade plan form. They generate thrust due to mechanically induced rotational forces causing the shape of the airfoil to exploit the Bernoulli Effect, generating lift at the "upper" or forward facing side of the airfoil. Another item you may confuse is a sail, which is also often employed as an airfoil. BTW, I'm a full scale pilot, 50 year RC operator, UAV pilot, not referencing multirotors and RC toys, and retired flight instructor.

 

[DerStig]

If you're an instructor you need to consult a dictionary and go back to school for a refresher in aerodynamics. Your students must be suffering terribly through your lack of knowledge.

I think Rotorman might need a 709 Ride....

 

[PatR]

Long over due.

 

[Rotorman]

Wow **** all of you. This wasn't personal. What kind of bull **** is this. I was having discussion and because you are wrong you go to personal attacks. What children. No wonder you fly fake aircraft. Makes it easy to just move on. What a bunch of douchebags


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[WilsonFlyer]

On a vertical lift aircraft, the blade/propeller becomes/is the airfoil. Aerodynamics 101. Sorry.

 

[Dragonflyerthom]

All props, rotors,wings are airfoils. Don't want to get into a pissing match but even a ruler which is flat on both side will generate lift if the AoA is changed. This is fundamental flight. Rotor man please don't get on the defensive. You nor I know everything. Just basic physics.

 

[DerStig]

Wow **** all of you. This wasn't personal. What kind of bull **** is this. I was having discussion and because you are wrong you go to personal attacks. What children. No wonder you fly fake aircraft. Makes it easy to just move on. What a bunch of douchebags

Awwww Rotorman you got you're feelings hurt when you were talking out of your ***. WE are not wrong WE know what we are talking about. You on the other hand don't exactly understand how lift works or is created. Seriously you need a 709 ride I'm not sure your local FSDO would be happy to learn that you don't know what you're teaching. As for flying "Fake Aircraft" well I'm a partner in a flight school and I fly several different aircraft (Kingair c90 with a Blackhawk conversion, citation X, Citation Mustang, grand Caravan, PC-12, DA-42, DA-62 and just about every single engine bug smasher out there)

So you might want to tone it down and hit the books. Because after that little outburst I really think the best course of action is a 709 for you