New Bird – Stable Exit and Neptune Questions

[Signo 0]

Hi, I did my first bird-dive and got hooked to it. After the dive, my BMI recommended a number of things to work on through a bunch of practice tracking dives. His comments include (1) a stable exit (during my bird-dive I ended up on my head on exit followed by a spin from which I recovered fine). He’d also like (2) a more stable deployment (during my bird-dive, I also ended up kind of on my head during deployment). Before wingsuit, I never really did tracking-dives, now I have made about ten of them and I have got pretty hooked to tracking.

Through tracking, I figured out how to have a nice wingsuit-style deployment position so that my original Sabre 170 does not open too fast. I still have two questions though:

1. How come that when I exit the otter in a wingsuit-style position I always end up kind of on my head. You see in the profiles of two tracking dives I attached speeds of 140 mph and 160 mph right after exit.
2. These profiles also show true air speeds of 72 mph and 82 mph during my slow track in a wingsuit-like position (these results are consistent with others I have). Can these readings be trusted? I wear my Neptune on my wrist, I tried wearing two Neptunes (one on each wrist) having comparable results between the two. Is there a better position to wear Neptunes to get accurate readings during track-dives or wingsuit-dives?

Thanks a bunch. Safe, long, fast, and slow flights,

Riccardo

[phoenixlpr 0]

Quote

1. How come that when I exit the otter in a wingsuit-style position I always end up kind of on my head. You see in the profiles of two tracking dives I attached speeds of 140 mph and 160 mph right after exit.

Do you mean head low or head-down?

[Signo 0]

The video I have seen of my winguit exit confirms that I am steep on my head. I have not seen any videos of exits during practice tracking-dives and next time I will ask the videographer to video my exit.

[KrisFlyZ 0]

What is your height? I got your weight from the wingloading and canopy size. How is your weight distributed? Do you have longish legs and a lot of weight around the torso?

Just a few things that might help.

The attitude of the body can be controlled relative to the horizon. Let us say you closed your arm wings and fully spread the legwing, it is possible to not get headlow or even go head high if you want to.

Try this without wearing your wingsuit(arms along the sides and legs spread) or wearing a small suit and at high altitudes to allow recovery in case of instability.

Kris.

[Signo 0]

You have a point. I am 6'4'' 225 lb with gear on. My weight is distributed in that I am pretty slim. The winguit I was wearing for my maiden flight was an original Classic that I checked out from my BMI. I plan to stay with this model or with a similar one (GTI as far as I know) for a while since as far as I understand these are good entry level suits.

The profiles I posted are profiles of my tracks with no wingsuit on. Only my freefly suit which is pretty tight. Next time I will go tracking I will try to exit as you suggest, with arms closed and legs spread and see how that goes. Thanks.

This I am posting is the profile of my only wingsuit jump. It shows a slow speed of 61 mph TAS and deployment speed of 106 mph TAS. More importantly the speed on exit of 127 mph TAS during the spins.

Thanks,

Riccardo

[KrisFlyZ 0]

I thought the logs from your first post were wingsuit jumps. Get really comfortable in the suit before worrying about any of the things I said.

Kris.

[OSOK 0]

Ok, I don't have the jumps nor have I jumped a wingsuit, but I've done lots of tracking dives wearing a GPS and I'm familiar with what it should show. My question is: what kind of "speed" is this that the Neptune shows? vertical, horizontal, 3d? And what the heck are you doing that you have such aggressive changes in speed?

[lurch 0]

Hey Riccardo.
Next time I'm out, we'll go over the video again, get your exits dialed and go up again.
You're going head low because you looked down. Would have made an awesome exit if you were freeflying.
All you gotta do to fix this is fix your gaze on the prop when you exit. Hop out sideways, keep looking at that prop as you drop away. This will roll your shoulders back and keep you head-high. Then you just kind of lie down on the air. Do this your next tracking dive, tell me how it goes.
I'm not worried about you going head-low next opening. Just keep your legwing closed tighter, thats all.
-B

Live and learn... or die, and teach by example.

[phoenixlpr 0]

Quote

My question is: what kind of "speed" is this that the Neptune shows? vertical, horizontal, 3d?

Think! What kind of speed can an barometric altimeter show???

[Signo 0]

Like phoenixlpr says, the Neptune detects barometric air changes from which the fall rate is computed. The profiles I shows are from my Paralog and they report fall rate in true air speed. That is the vertical speed of the skydiver during the dive at the elevation he is at. Another way to present the data could be to show the SLAS. That is the vertical speed of the skydiver referred to sea level elevation.

What is the brand and model of the GPS that you are wearing? Does it have capability to export profiles in to Google Earth?

The profile of tracking jump 209 shows approximately 70 mph of fall rate change from 10,000' and 9,000'. The fall rate goes from 140 mph to 70 mph in approximately 5 s. From the note on my logbook, what happened there, I think, is that I changed the attitude of my body during the track from a steeper head low to a very slow head high track. In other words, I think that as the angle of attack of the body widely changed in short time I did slow down. I was not looking for this effect, but next time I will certainly try to play with that. Thanks for the comment.

Safe and fun jumps,

Riccardo

[Signo 0]

Hi Brian,

Great Comment. You are so right, indeed I do not recall seeing the prop on exit in my last 200 jumps.

Next tracking-dive after spotting I will try the exit you pointed out.

Look forward to next flight. Soon I will have Don take care of my corners and I will buy some hard risers inserts. I do not feel comfortavle with a 100'' bridle because my BOC is free-fly tight and I do not want to loosen it up. Yesterday I got an alomost new Cypres 2 to replace my dying Cypres.

I look forward to seeing you and the flock again at Pepperell. Have fun this weekend in Florida.

Riccardo