Bernie Hunt spreadsheet

[piecost]

Fellow forum members,

Can anyone post supporting documentation for Bernie Hunt's static Stability spreadsheet?

Cheers

[Olbill]

Don Slusarczyk can.

[Hepcat]

Piecost,
Reg Boor did most of the clever stuff on Bernie's Indoor Design spreadsheet but how much he will have records or memory of after all these years I don't know. Reg was an aerodynamicist with Avros all his workinglife.  He is regularly seen Indoor Flying, almost always nowadays with Scale Models.  So far as I remember the tricky parts in the calculations were things like downash estimates which is where Reg did a lot of work.
John

[piecost]

Thanks for the reply John. I have met Reg once, when he flew at the Brabazon Hanger in Filton,  but I wasn't aware of the spreadsheet then. I was hoping to find a published paper along the same lines as your propeller design review, which enabled me to reverse engineer your spreadsheet. I will have to brush-up on my vortex theory to unpick this one.

Cheers

Tim

[Soc]

Hi Piecost

I too would like to see any supporting documentation for the BH spread sheet.

I got a copy a few years back and reverse analyzed it to work out the algorithm.

Most of the steps follow conventional aerodynamic theory and mathematical modeling methods,
but there are a few oddities along the way, which might be mistakes or fudges or something else.

There have been a number of articles on modeling low RE drag in the NFFS symposiums over the years
and I think ideas from some of these are used in the spread sheet,
but so far I've not been able to relocate the bits I think I read.
Its possible that the relevant material was in an article that I read in an on-line collection somewhere.

I'd be very happy to discuss the matter with you and send you my notes.
PM me if you would like to take this further.

Sean

[frash]

Has anyone asked Bernie? The last that I heard was that he retired from indoor competition but was flying RC sailplanes outdoors.

Fred Rash

[Soc]

Piecost

I sent you a PM with a contact address.
If you contact me via that address I can send the notes I've managed to dig up.

There are a few reasonably coherent pages that seem to cover everything.

Sean