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Yes, I was pulling some Gs. Why do you ask?

ChiefPilot

Well Known Member
I've seen this occasionally before but this was the first time it happened while a camera was pointed at it. The conditions have to be just right, but it's pretty neat when it happens.

50228595916_f5b4a1aa62_b.jpg


The curious thing is the unpredictability of it. Clearly the temperature and the dew point need to be really close, and the humidity has to be sufficiently high. But I had the opportunity to "play" with these a bit at that time.

I found that modulating pitch to increase/decrease load factor impacted it (of course) but also yaw affected it. I could skid towards or away from it and it'd disappear but when the ball was centered it appeared pretty consistantly.
 
Very cool that you got this! We can learn a lot from this.

Is this the old-style tip with the unswept side edge that follows, more or less, the contour of the upper surface?

I'll say more this evening when I have a bit of time.
 
cooling

low pressure cools the air until air temp is below dew point. Has to be quick otherwise heat from surrounding air keeps it too warm.
 
Very cool that you got this! We can learn a lot from this.

Is this the old-style tip with the unswept side edge that follows, more or less, the contour of the upper surface?

I'll say more this evening when I have a bit of time.

Yep, exactly - they are the old school "Hoerner" style wingtips. The lights are all contained in the cutout under the lens so there isn't anything on outside/bottom of the wing tip either.

Drop some knowledge bombs on us :)
 
Prop Trails

Here's a similar effect from the prop (prop contrails) that was captured during a takeoff with Mike Seager in Vernonia.

DSC_8224cropped.JPG


DSC_8225Cropped.JPG


Skylor
 
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I've seen this occasionally before but this was the first time it happened while a camera was pointed at it. The conditions have to be just right, but it's pretty neat when it happens.

50228595916_f5b4a1aa62_b.jpg


The curious thing is the unpredictability of it. Clearly the temperature and the dew point need to be really close, and the humidity has to be sufficiently high. But I had the opportunity to "play" with these a bit at that time.

I found that modulating pitch to increase/decrease load factor impacted it (of course) but also yaw affected it. I could skid towards or away from it and it'd disappear but when the ball was centered it appeared pretty consistantly.

chemtrail!!!???!!
 
I'm pretty sure that is smoke from his smoke system.

Nope. I saw the same thing from inside the plane when we cycled the prop for runup. It was a very damp and cool day at Vernonia. As the prop cycled, we saw FA-18 style clouds form at the middle of the prop blades. We also had a touch of carb ice taxiing out. I'd never seen that with a Lycoming before. I guess the sump wasn't warmed up enough yet to heat the induction air.

Ed Holyoke
 
Yep, exactly - they are the old school "Hoerner" style wingtips. The lights are all contained in the cutout under the lens so there isn't anything on outside/bottom of the wing tip either.

Drop some knowledge bombs on us :)

I started a separate thread discussing Hoerner tips and why they work so well. Nice picture here illustrates one of the main effects.
 
Nope. I saw the same thing from inside the plane when we cycled the prop for runup. It was a very damp and cool day at Vernonia. As the prop cycled, we saw FA-18 style clouds form at the middle of the prop blades. We also had a touch of carb ice taxiing out. I'd never seen that with a Lycoming before. I guess the sump wasn't warmed up enough yet to heat the induction air.

Ed Holyoke

The stuff in the picture is definitely smoke.
 
Hi Brad,
Something I haven't seen before are pins instead of bolts installed in canopy frame to hold the rollers. Seems like it would definitely help in certain emergency egress conditions. Do the red streamers get in the way at all?
Thanks
 
Hi Brad,
Something I haven't seen before are pins instead of bolts installed in canopy frame to hold the rollers. Seems like it would definitely help in certain emergency egress conditions. Do the red streamers get in the way at all?
Thanks

No, in fact the ribbons are pretty stout and the idea is that if I need to step out, I'd grab the ribbons to pull the pins, unlatch the canopy and slide it back an inch or so then push it up. The wind blast should rip it away, at which point I'd unbuckle and step (I've practiced this sequence a bunch of times in the hangar so it's near muscle memory should I need to actually do it).
 
When the conditions are right here in Oregon, we see this sort of effect pretty frequently.
 

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