Vortex Ring State (Settling with Power)

[Ollie West]

Hi all, apologies if this is the wrong area to post this thread topic (I'm new here).

I'm an undergraduate aerospace engineering student and I'm researching areas to conduct my research thesis in for my final year. I like the idea of doing it in Vortex Ring State for rotary aircraft. The phenomena isn't very well understood and causes serious accidents, even in the 21st century (Brought down one of the helicopters carrying the special forces team getting Bin Laden).

I have been doing research online to find out how much is currently understood about the phenomena, I'm hoping to capture effects that happen just before the vortex is induced so a warning can be given to the pilot to react (similar to stall detection on an aircraft wing). Or design a deployable device to disrupt the vortex (such as a winglet).

Can anyone recommend a good source of knowledge for this area? I have googled and read most published papers/articles. Or tell me how much is known about the effect? What is currently done to detect it? etc.

Thanks.

Ollie.

[Peter H]

Ollie West (http://www.pprune.org/members/411744-ollie-west)
Hi all, apologies if this is the wrong area to post this thread topic (I'm new here).

Try the rotorheads forum.

Regards, Peter

[glum]

The V22 suffers really badly from it, and they have a warning system. Perhaps do some research on what they have done to develop this system.

[Senior Pilot]

Ollie, try reading Vortex Ring/Settling with power (merged threads) (http://www.pprune.org/rotorheads/116124-vortex-ring-settling-power-merged.html) which has lots of discussion :ok:

[Ollie West]

Thanks guys.

glum, could you point me in the direction of this warning system?

Thanks.

Ollie.

[Peter H]

Ollie,

If you've seen it, fine. If not, it's sitting in your pprune message folder.

Regards, Peter

[Ollie West]

Thanks Peter.

Ollie.

[ShyTorque]

The phenomena isn't very well understood and causes serious accidents, even in the 21st century (Brought down one of the helicopters carrying the special forces team getting Bin Laden).

Did it, really? Have you read the accident report?

I'd say that VR doesn't cause anywhere near as many accidents as does over-pitching/running out of power.

The two are sometimes confused, even by helicopter pilots, let alone the media.

[FlightPathOBN]

Ollie,

Check out Optical Air Data Systems, they have a product for helo landing, not really ring vortex as shown, but they may be working on that as well...

LandSafe (http://www.oads.com/programs/landsafe.html)

not many Companies use a Corsair for their test platform (http://www.oads.com/aviation_operations/vought-f4u-7-corsair.html)!
http://www.oads.com/files/imagecache/sidebar/files/Corsair.jpg