[WIP] The Flying Brick Restarted

[whale2]

On 1/20/2021 at 10:24 AM, Seasider said:

As an aeronautical engineer by degree and an automotive engineer by career I’m very interested to see if this will ever fly.

Having built in the past a RC airplane I can remember how light they typically are and from your wing a fuselage construction all I can see is weight and more weight. So I’m very curious about how you are going to solve the thrust/drag & lift/weight issue.

All I ask is when you do finally get to attempting a first flight please do video it as personally I can’t see it having a successful flight.

 

Indeed, weight is the issue. The idea is to overcome it with sheer raw power and speed. It is overweight by about 2 kg compared to normal RC models with similar wingspan, definitely will have greater stall speed.

 

On 1/20/2021 at 10:16 AM, Brickend said:

How much does the mighty brick weigh now?

About 5.4 kg

Anyway, tested motors parameters with watt-meter. I was able to get 48 A on the test stand before, but now I'm getting only 42 with 7x4x3 prop (and obviously less thrust). Tried all possible combinations of whatever possible (batteries, pull-push swap, etc). Managed to get 50+A with 7x4.5x3 prop, but I've got only one of such.

[Seasider]

But weight does not equate to power, you need to get your lift right and using a brick built wing you may find it’s not the right shape or smooth enough to get good lift from, you may just get a load of nasty drag and separation!

[whale2]

On 1/22/2021 at 2:09 PM, Seasider said:

But weight does not equate to power, you need to get your lift right and using a brick built wing you may find it’s not the right shape or smooth enough to get good lift from, you may just get a load of nasty drag and separation!

Then I'll opt for making it so ugly, the earth will start repelling it.

But seriously, power should get me more speed and more speed means more lift even with not so much of an efficient wing. Also, I did a crude test with sticking ton of short threads and blowing into the wing. Don't have a video, but the flow behavior seemed reasonable - re-attaching after that step, separation on higher angle of attack as expected and such.