Lupo

I said I was moving on to build an own-design glider next...so here it is. The design might change as progress is made and problems identified, but this is the general idea. It will be 1.86m span and 1.2m long - using 36" balsa for the wings and 48" for the fuselage. This makes it a similar size to the Phase 5 but it will use a modern wing section in order to (hopefully) perform better.

The wing section is TP42 at the root transitioning to TP29 at the tip. These sections are symetrical and 9% thick which is e slippery than the Phase 5 which has a section that looks like Eppler 374 (root - 10.9% thick) transitioning to NACA 0009 (tip - 9% thick).

Foam cores are cut and a 1/16 ply shear web added by cutting the wings in half and then gluing back together again.

A while back Brian was explaining that his building board was warped. I have a few work surfaces in my workshop and one of them is definitely level...I use this for general building and for cutting my foam cores on. But when I need to pin things down I use portable boards made from 18mm MDF with pine screwed to the back. The top surface then has cork tiles glued on. These have remained true for about 15 years. An advantage of them being portable is that items can be left to dry anywhere leaving the workbench free for other tasks.

Looks interesting Mike, any thoughts on offering the plans/ foam wings etc to a wider market?

AlanF wrote: Looks interesting Mike, any thoughts on offering the plans/ foam wings etc to a wider market?

The plan will be shared when it's complete...both plan and model are being 'built' simultaneously.

If it flies well I might consider providing foam wings, but it would be up to the buyer to skin them because it is too time consuming for it to be a cost-effective process. It would be a lot cheaper for someone to buy a foam wing from a commercial outfit.

I had intended to do another build log with this one, but the website failure last weekend meant I got ahead of myself and decided to leave things quiet until I'd made progress. I'll use the images I took along the way to write an article for one of Phil's newsletters (and also for the Wessex newsletter). In the meantime, if you have any questions please ask. Last images shows it next to the Phase 5 for comparison. They are about the same length and wingspan but the Lupo has a much skinnier fuselage and a higher aspect ratio wing.

on 25th April Mike said "I was moving on to build an own-design glider next " then he made wait nearly 8days before the finished article

Pull your finger out next time mike !!!!! :sick:

MikeSeale wrote: I had intended to do another build log with this one, but the website failure last weekend meant I got ahead of myself and decided to leave things quiet until I'd made progress. I'll use the images I took along the way to write an article for one of Phil's newsletters (and also for the Wessex newsletter). In the meantime, if you have any questions please ask. Last images shows it next to the Phase 5 for comparison. They are about the same length and wingspan but the Lupo has a much skinnier fuselage and a higher aspect ratio wing.

All I can say is WOW! :blink: Do you need any more Balsa?

It's gone very quiet here.

Lupo had it's maiden flight a while back but I've been busy and only just had time to edit the video

...and shortly after Lupo came a sibling, Rolo. Very similar in that they both have the same wing and tail planform. But Rolo has a built up plug in wing whereas Lupo is a one piece foam wing. They have different wing sections, Lupo is symmetrical but Rolo has a little camber so should perform a little better in light winds. And Rolo has a slightly shorter fuselage. The reason for this is mainly to reduce the tail moment in order to reduce the amount of lead needed to balance it for the correct centre of gravity. But I also took the opportunity to make the fuselage sides from 36 inch sheets.

Both flew in the strong winds at White Sheet yesterday. They fly sufficiently different to have made it a worthwhile project. It's unclear which is my favourite.