kimba

Hi Carsten

I have tried running the Viper on the stand with the wheels up and have found the following (Viper has 160SX new motor)
On my Viper when the wheels are down I close the main wheel doors via the sequencer when I run the motor in this configaration on the stand the Canopy is ok and you can feel quite a lot of air coming in through the noeswheel.(I do not have a bypass).
When the wheels are all up and doors closed I was not game to take it over 1/3 throtle as the sides of the canopy (not the frame ) were being sucked in and I was afraid it was going to break. ( see photos ). So I cut out the air brakes as per photo and made up a frame and glued in some alloy sive wire and painted it all flat black.I then put it on the stand again and tried it. This time with the motor running flat out it only moved the canopy a very small amount so I am pretty sure that it will be ok. Also we should bare in mind that the plane is not in the air so you do not have the forced air coming in but I am not sure whether this would make any difference or not. We have several Vipers flying here and they have not had any trouble with the canopy all are using the Jetcat 160 This makes me wonder if some of the canopies are of a thinner grade on the sides. On my canopy I have put an extra pin at the top of the frame at the front and 2 pins on the sides of the frame half way along it also has a piece of spruce going across the conopy between the 2 pilots. (May be Anton or John could check the quality of the canopies )

Hope this helps Bronte
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