Boulton Paul, summer project 2019 bis

​

Span:    750mm Span

Weight: 1000 gr

EDF:      70mm 12 blade (Hobby King)

Motor:   QX 2600kv

ESC:      60A 6s

Batt:      4s 3700mAh

 

In the past month I have build a larger version of the Boulton Paul, I just scaled up everything 25% for this one. This brings the wingspan up to 750 mm and with some adjustments there is room for a 70 mm EDF. A ChangeSun 70mm 12 blade with a 2600kv QX-motor I still had lying around, it did its job more than properly in my Laser Arrow on 4S. The Construction is identical to that of the smaller ones so I can't tell much new about that. Apart from the fact that this time the wing is not made up of 3 segments, but 6 segments. A delta wing is not always easy to cut with a hot wire, there is always a lot of burning off of foam at the tip due to the large speed difference. That is why with the small P111 it became 3 pieces, then the difference is smaller, but with the larger one it turned out not to be sufficient, so it became 6 pieces. You do have some work with gluing them but afterwards you have a nice delta. The model is again covered with fiberglass on the body and paper on the wings. At the height of the hinge line of the ailerons I have placed a strip of nylon fabric under the paper. Once the paper is dry, I cut the foam away from below into a V shape down to the nylon and you have an instant hinge as with a full composit model. It is by far the simplest way to make hinges on a foamie that I have already tried. Sometimes a person wonders why it took so long before you came up with it.
The model was ready for the maiden flight for a few days but the weather was not very good so I had to wait. In contrast to the previous days, yesterday it was calm and dry weather. So I had to know if the Boulton Paul would fly, normally that should not be a problem since the smaller one flies flawlessly. I went quickly to an open field nearby. After a good throw, the Boulton Paul convincingly climbed away. A bit of trimming was needed on both axes, but then the P111 flew as expected. The first flight was cruising around to feel the models handling, landed without problems after four and a half minutes. For the second flight the trows were somewhat reduced and 25% expo was set on elevator and ailerons. Now I went full speed, the model goes endlessly vertical, the thrust weight ratio is clearly more than 1/1. I should measure it sometime. Horizontally, the P111 is pretty fast and after a dive it is ridiculously fast, I'm going to love this thing. Since I have balanced the EDF it runs very smoothly, with a fast flyby you almost hear nothing but the whizzing of the model, as if it is a glider. I hope I can make a video soon.

 

 

​