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Hi all. I have a question about my mojo openings. Here goes

It is a Mojo 240, unvented canopy produced in 2001. It has 450 jumps on it with a complete inspection and line-replacement at 350 jumps. Both the canopy and lines are in good condition. It is fitted with a fine mesh slider, standard 1-pin bridle (container is a prism2, canopy fits perfect in it) and I use a 36' fine mesh pc. The brake lines come with one brake setting and it is always jumped slider up.

Now, over to the opening

When I deploy, the canopy extracts to line strecht, it starts inflating and the slider comes down in fine manner. Now, fully inflated with the little normal surge you find in an unvented canopy during the first seconds of flight, it dives down. And I mean dives, really steep, giving me a big pendulum sving. Fully pressurized and flying the canopy will dive from 45 up to around 60 degrees forward from normal flight position. It comes back to a normal position and flies at a normal glide angle within 2-3 seconds, regardless if if fire my brakes instantly or leave them stowed. After the opening the canopy flies normal, breaks stowed or not.
Now what really weirds me out is that this is non-consistent. Percentage-wise it is close to 60-40, normal opening/dive opening.

Here are some factors

Dive openings do not occur when I fly wingsuit (which is also a bit weird since the glide angle of the wingsuit puts me on my back during opening, creating a little pendulum effect)

All have been on terminal track jumps with and without tracksuit
All have been on heading
They occur under deployment both in full track (steep with very high speed) and when I box to reduce speed, deploying in a flatter bodyposition.
The dive is violent and fast, the force from it tosses the bridle and pc over and in front of the nose.
It returns on heading, flying nice.

I can't get the canopy to dive as steep as the steepest opening dives by pulling front risers, even from a near stall. I can do it with a hook turn but that is not the same. On the opening dive both front and rear risers seem to be fully loaded and in perfect symmetry, just as when you hang in your harness during normal flight.

I also jump a fox 245 vented and a trango 245. Same pack job on all three but never seen tendencies to dive openings on the other to. They open nice. I have 20 jumps on the mojo.

Any thoughts on what could be causing this, or if this is a thing with the mojo?

Thanks, Magnus

I had similar openings on a skyjumping canopy when it was on it's way out of trim.
I know you mentioned that it was retrimmed in the last 100 jumps, but I would suggest checking the trim against manufactures specs, physically measure each line.
Also, it sounds as if it is opening at a stall, hence the surge. Maybe check the brake set point too.

just a thought...

is there a correlation between this diving behavior and a tailwind?

Lateral winds have no influence on terminal deployments.
Sounds like a stalled config deployment.
Take care,
space

I agree with you Stacey, from the info provided it sounds like the brakes are too deep.

Thanks guys, Im gonna check that out

Try this: bring a marker pen on the next jump. Bring down the toggs to just before stall and mark it at the ring position.
do this as many times as possible. Get the average mid point and place the new setting 8cm above.
I can give you tips on how, if you need for marking.
take care,
space

Hei Magnus
I think you must have bought this canopy previously used? you say there is only one brake setting, I would bet that you don't have a lot of jumps on this used canopy, and the person that you bought it from set his own custom brake setting? I would guess that there is either a weight difference?or, since you say it has a new lineset,it is possible the problem originated there, but it really sounds as if the brake setting is too deep either for the wingloading, or just because of the new lineset. I met you last season, I will be visiting soon, i would like to touch BASE with you, Regards,B.

"It comes back to a normal position and flies at a normal glide angle within 2-3 seconds, regardless if if fire my brakes instantly or leave them stowed"

Why would the presumption be that it's because of the DBS?

The fact that this surge does not occur on WS jumps in interesting.

I'm new so I really appreciate this discussion.

Thanks.

PC capture is the key. Over the nose or hanging in the steering lines is the clue. Occurrence is only apparent to the observer. Not the canopy. The surging is the canopy wanting to fly but the brakes wont let it. Dial it in. DBS.
CR has the best info for DBS. Mine is better, but not by much. Take care.
space