High speed AND high performance wings - MISCONCEPTIONS
Posted: Thu Nov 01, 2007 11:11 pm
What is a high performance wing? One with 90mph+ vne??? NO NO NO.
Quoting from the second hand saturated thread...
BUT this thinking creates a huge misconception, one fast trike wing is NOT the same as another. Similarly a high performance wing is NOT neccessarily a fast one!
An example of some research done by the British showed that Wing A at 30 degree bank stalled at 35, 60 deg @ 47 and a slower larger wing 30@35 and 60@52. The first being capable of over 90mph, 2nd 75mph.
On another brand, wing capable of 90+, stall 30@41, 60@63. We're seeing alot of this creeping in that speed is better and because my wing can do 90mph it's good. Even if a local highspeed wing is produced remember it's NOT just speed but how it handles at speed and banking.
Trike wings also stall at lower speeds than 3 axis theory would dictate when weight is added, and NOT all trikes increase the same. Infact many of the materials used noawdays are not just for UV or strength, but for the flexing and clean shape attributes too, not to mention pressure retainment.
Why am I ranting? An acquaintance of mine from the US had a prang - he's fine but plane is a writeoff. Attempting >60 degree bank. The wing he had is available locally and even if he pulled in bar and got speed up he still would have had hassles with the higher stalling speed at his angle and his trike's weight at the time.
What does this mean? Simple if say your wing cruises at 60mph and at MTOW 30 degree bank stalls at 40 and 60 deg 65mph, you'll need atleast 70 for safe turns. However what makes a high performance wing "safer" is that under the same conditions 30deg@43 and 60@50. The same wing at 90 stalls at 61. You almost can't stuff it up.
I've got two manuals of wings both have same VNE's 1mph dif in stall straight and level but HUGE variances when banking and even larger when loads are added.
Yes I can hear people saying but the wing is limited to 60 bank. When u have an engine out and you need to bank hard atleast you'll know what speed is safe or when posing for that wingover shot that is so popular nowadays.
Sorry if I didn't explain well, I'm just sad, happy (that he's ok) and peeved by this accident that could've been avoided.
Infact I'm reminded of accidents in the past here locally where it was said the pilot did too steep an angle low level - thing is plane doesn't know it's low. Perhaps we just aren't aware that higher up we were losing altitude...
No I'm not anti GT450 - quite the contrary, but please find out what your stall speed is at various loadings and bank angles - sometimes pulling bar before entering will not be enough.
Many trikers go 3 axis route not just for speed but for stability, Demon has long been advocating the advantage of true "high performance" wings - not specifically fast ones. My guess is we'd have more trikers if they flew hp wings.
I've got a test manual for one of the AirCreation wings and although it was tested to over 200km/h without ANY wallowing tendencies the VNE is only 140km/h. As my mate has now learnt the safety envelope / % is not the same across brands, I'm not saying they're unsafe just, less room. And now take a high Density A...
Read those manuals and test reports - please
Quoting from the second hand saturated thread...
I won't mention brands yet...Carel wrote:3. Speed. Trikes are getting faster and faster. (Point 2) Only a handfull of pilots really fly to look at the scenery below him. Most pilots now fly long distances on fly ins and cross countries. Speed now is an issue as most of us do not really have time to do something in 3 hours while it could be done in 2 hours. This explain why pilots are upgrading and the huge transgression to three axis.
BUT this thinking creates a huge misconception, one fast trike wing is NOT the same as another. Similarly a high performance wing is NOT neccessarily a fast one!
An example of some research done by the British showed that Wing A at 30 degree bank stalled at 35, 60 deg @ 47 and a slower larger wing 30@35 and 60@52. The first being capable of over 90mph, 2nd 75mph.
On another brand, wing capable of 90+, stall 30@41, 60@63. We're seeing alot of this creeping in that speed is better and because my wing can do 90mph it's good. Even if a local highspeed wing is produced remember it's NOT just speed but how it handles at speed and banking.
Trike wings also stall at lower speeds than 3 axis theory would dictate when weight is added, and NOT all trikes increase the same. Infact many of the materials used noawdays are not just for UV or strength, but for the flexing and clean shape attributes too, not to mention pressure retainment.
Why am I ranting? An acquaintance of mine from the US had a prang - he's fine but plane is a writeoff. Attempting >60 degree bank. The wing he had is available locally and even if he pulled in bar and got speed up he still would have had hassles with the higher stalling speed at his angle and his trike's weight at the time.
What does this mean? Simple if say your wing cruises at 60mph and at MTOW 30 degree bank stalls at 40 and 60 deg 65mph, you'll need atleast 70 for safe turns. However what makes a high performance wing "safer" is that under the same conditions 30deg@43 and 60@50. The same wing at 90 stalls at 61. You almost can't stuff it up.
I've got two manuals of wings both have same VNE's 1mph dif in stall straight and level but HUGE variances when banking and even larger when loads are added.
Yes I can hear people saying but the wing is limited to 60 bank. When u have an engine out and you need to bank hard atleast you'll know what speed is safe or when posing for that wingover shot that is so popular nowadays.
Sorry if I didn't explain well, I'm just sad, happy (that he's ok) and peeved by this accident that could've been avoided.
Infact I'm reminded of accidents in the past here locally where it was said the pilot did too steep an angle low level - thing is plane doesn't know it's low. Perhaps we just aren't aware that higher up we were losing altitude...
No I'm not anti GT450 - quite the contrary, but please find out what your stall speed is at various loadings and bank angles - sometimes pulling bar before entering will not be enough.
Many trikers go 3 axis route not just for speed but for stability, Demon has long been advocating the advantage of true "high performance" wings - not specifically fast ones. My guess is we'd have more trikers if they flew hp wings.
I've got a test manual for one of the AirCreation wings and although it was tested to over 200km/h without ANY wallowing tendencies the VNE is only 140km/h. As my mate has now learnt the safety envelope / % is not the same across brands, I'm not saying they're unsafe just, less room. And now take a high Density A...
Read those manuals and test reports - please