VG's on a LightWing

[Guest kermet]

Hello All,

 

im looking for information if anyone has fitted vortex generator on a lightwing, i have a simalar problem to other's and have a short paddock airstrip that i fly my Bantam from but wish to upgrade to a lightwing,

 

there's lots of info on these VG's and they sound great but havnt found anyone who fitted them to the GR-582

 

http://www.hallwindmeter.com/vortex.php

 

Cheers

 

Brett

 

 

[River]

VG's and Lightwings...

 

G'day Brett,

 

I recall a couple of years back talking to a pilot at 'The Great Eastern Fly-In' at Evans Head, northern NSW who owned a GR912 tail-dragger Lightwing.

 

He indicated a friend of his who flew out of Casino (Northern NSW) in a similar Lightwing had fitted VG's to the wing and fuselage area just to the rear of the cockpit area with considerable improvement. Reckoned he gained some 8 knots extra cruise speed and around 200/300 fps improvement in climb performance.

 

Cheers,

 

 

[TechMan]

I take it the aircraft had the relevant Engineering Order to fit the VG's onto the lightwing, if it was 25 registered?

 

;)

 

Chris

 

 

[River]

Of old dogs and Lightwings....

 

I take it the aircraft had the relevant Engineering Order to fit the VG's onto the lightwing, if it was 25 registered?;)

Chris

G'day Chris, Yes, very good point... :;)2: I ponder as to that myself too and asked via the 'old' RAA forum site when it was running but had no replies. Hmmm.

 

Whilst it would be quite possible to improve the drag on the lightwing with the possible use of VG's the performance figures being spoken about did seem somewhat high on the improvement scale.

 

It's always disappointed me that further development of the Lightwing did not take place as I believe it has the basics for lending itself to a 'Mk2' version as a damm good 'rag an bone' aussie utility aircraft.

 

Cheers,

 

 

[facthunter]

Vortex generators.

 

Proponents of these devices claim improvements of various kinds, generally related to smoothing of airflow (separation....Boundary layer control). No doubt they perform an important function on occasions. I have seen a full set fitted to the wing of a Piper Navajo. (Laminar wing section ) to reduce stall speed. Claiming no drag penalty, indeed it claimed an improvement.

 

The "S" duct (intake) for the centre engine of the Boeing 727 has them installed internally and if several are missing, the engine stalls on high power.

 

The FIN of the same aircraft has them all the way up both sides, so they definately work, in the right places. Interesting!.. Nev...

 

 

[CLAYT]

I have vg's on

 

I have vg's on my GR912S.Main improvement is in hold off,it doesn't seem to dump me on the deck like it did before we fitted them.

 

 

[Guest avi8or]

how did you work out where to place the vg's

 

 

[Guest Maj Millard]

The standard GR 912 wing with the factory 2 stage flaps will get you out of anywhere, loaded or unloaded, on the first stage. You can also slow it down safely below 50 kts and drop it in supershort. Obviosly there is no substitute for power for short take-off performance, although they do go well with the 582 as long as you keep them light.

 

I attempted to reflex my flaps for better cruise speed, ala the flaps on the GA wing, but physically you can't do it on the standard wing. On the GA wing reflex flap is good for an additional 6 kts or so. I have however reflexed my ailerons quite a bit on the standard wing, and did get a noticable increase in cruise speed, without any decrease in aileron effectivness.

 

The trailing edge of my ailerons fly about 1" above the TE of the flaps. I normally see cruise speeds above 80 kts at altitude at 4800 rpms on the 912s.

 

Don't have any experience with VGs, but do know their effectivness is mainly felt in the lower speed range, and I doubt if they would have much effect on increasing cruise speed. The GR wing is just a basic Clarke Y airfoil section and I wouldn't be surprised if somebody somewhere hasn't tried VGs on something somewhere, with the Clarke Y. A good google search would probabily turn up some usable info, or figures........

 

 

[David Alford]

Lightwing with VGs

 

I don't want to mention names, but I know of one person with a Lightwing who was quite happy with the improved slow speed performance after the VGs were installed. This was the plastic type distributed in Australia and recommendations of where to place them came with the kit.

 

 

[Guest ledsled]

performance changes

 

Having flowm the GR Lightwing wing before and after VG fittment, the stall speed reduction is at least 10 per cent for about an hours work.No noticable change to cruise.Would be the same for 582/912 as it is the same wing.

 

 

[Guest Maj Millard]

Querty would be the man to talk to on VGs or John Gilpin at Kilcoy...both forum members.

 

 

[Guest ledsled]

John Gilpin helped me fit the VGs for the purpose of evaluation on the Lightwing. I suspect he will quote my numbers. Querty also agrees after trying them.

 

 

[Guest Maj Millard]

I have flown the Savvy VG, and yes they do work, especially landing time. My LW is a GR wing with flaps, so it already jumps off the ground even heavily loaded, and landings are nice also with no float, like the standard wing. I'm not sure VGs would do a lot in my situation, other than get in the way when fueling or washing the aircraft. What do you think ?.

 

 

[Guest Qwerty]

Major,

 

From my experience (and reading) it seems that VGs work well on high lift, "slow" sections. If I were pushed for an opinion, I would suggest that on the GA Lightwing, you will pick up a noticeable decrease in stall speed, improved aileron effectiveness at low speeds and possibly full aileron effect well into the stall, no detectable effect on cruise and the stall will probably become 100% predictable, it is likely that the unpredictable and unbalanced stall will become completely benign.

 

The VGs do need to be installed in the right place though.

 

PM me with a landline number if you want to discuss it.

 

Cheers, Qwerty

 

 

[Guest Maj Millard]

Querty, I don't have a GA, I have a GR wing with two stage flaps (special option). I would agree though that the VGs would go very well on a GA wing. I really don't know how many GR wings Howie did with flaps, like mine. My S/no is 140 (2000 model) he put the jigs up in the rafters about then, don't know how many highwings he built after mine. I really should call him and ask.........................................................................................