Well I was able this past weekend to log another 3 flights on this airplane and all I can say is that it flies very forgiving. At 12 lbs AUW you can turn hard and slow and it kind of drops the nose a little and remains flat. No snaps or anything. I've been able to slow it down on final to the point that it will drop our of the sky flat on the gear without tip stalling. I will try to get a few more flights on the Viper as it is before I try to up the capacity of the packs. Max I will go is 5000's this should give me 6 minutes of flight so I can live with that. I would like to try this on my aggressor.

that good news Jeff. hey did you move? i thought you were closer to PRADO

Work address

Hi Jeff - I am working on my Ultra Viper - and most likely going with a JetFan-90 based on your experience. I saw how you moved the fan way back and added a section of tube to transition down to your 90mm fan. A couple of questions.

1. What did you do with the hole in the center of the inlet duct?

2. What did you build the duct out of from the inlet to the fan?

Thanks.

- Rob

The whole in the center remains unchanged. As for the ducting I simply made a flat section of glass. Get some plexi and then you wax it any household wax will work. Let the wax setup, then give one last coat then your ready to lay a piece of glass cloth down and then use a resin of your choice. I usually let it set up for 4 hours or so and then when not fully cured I will roll it round and then put rubber bands around the roll. Let fully cure for another 24 hours then cut to desired length for your particular ducting needs. Once fit is good. I then go and add carbon tow to ensure I don't suck in the ducting. It may be overkill but I know I'm solid and don't have to worry about it. Going to 90mm worked out very well for me. And provides solid flight performance.

Good luck with your build.

Cool - thanks Jeff.