Bearhawk 5

[Nev]

Does anyone know if the BH5 wings are identical to the BH4B ? Is there any change to the structure or materials ?
Is the BH5 rated at the same 4.5G limit ?

[Mark Goldberg]

The Model 5 wing has a .040 spar WEB. The Model B has the .032 web as shown on the plans. Mark

[Utah-Jay]

Who thinks Nev should build a Model 5 so we can watch?

Or are you just wondering if you could put different wings on

[kestrel]

I'll watch!

[Redneckmech]

The Model 5 wing has a .040 spar WEB. The Model B has the .032 web as shown on the plans. Mark

Is this a recent change or just on the factory built spars? My BH5 plans show a .032 web thickness.

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[Nev]

What is the G limit on the front page of the plans ?

[triumphantduke]

first page model 5 shows: +4.5/-2.5

[Nev]

Who thinks Nev should build a Model 5 so we can watch?

Or are you just wondering if you could put different wings on

Haha. It's very tempting and it does look like a good aircraft. I'm curious to know what the air frame and wings weigh by themselves, compared to the BH4B. Obviously it will be a bit more, but maybe not much. The longer fuselage might increase the yaw stability, and having a bit more shoulder room is never a bad thing (Heck on the Boeings we had about 3ft between shoulders and that was still too close ).

I was also wondering then if the aircraft could be built for a very similar weight as a 4B, by using say an IO540. Is there a CG issue with using a smaller 4 cylinder engine, say an IO390, and using it as a 4 seater ?

[Battson]

I understand Colin's first BH5 is lighter than many Bearhawk 4-Place / Bravo aircraft, at around 1450 lbs. So it can be done.

I guess you have to be religious about the weight savings to achieve that, Colin is a master.

[flashf16]

FWIW the prototype Mod 5 empty weight is 1512, and Collins second Mod 5 came in at 1597.

[Nev]

I wonder if it had the interior installed before the W&B. Some of the photos appear to show it without one.

[kestrel]

The prototype had a very sparse interior. You were looking at the fuselage tube and inside of the outer fabric when inside it.

[Mark Goldberg]

.I apologize for posting wrong answer to Nev's question. We did use .040 for the spar webs on ONE set of Model 5 wings that was for a special purpose plane. But the normal Model 5 wings are identical to the Model B 4 place wings. At the kit factory we do always use the one piece, milled (out of .250 plate) cap strips for all Modell 5 wings. And not always do that on the Model B wings. But the plans are the same and the wings are normally identical. Mark

[Redneckmech]

Thank you for that clarification Mark, I was completely re-thinking the .032 spars I just cut.

[Utah-Jay]

.I apologize for posting wrong answer to Nev's question. We did use .040 for the spar webs on ONE set of Model 5 wings that was for a special purpose plane. But the normal Model 5 wings are identical to the Model B 4 place wings. At the kit factory we do always use the one piece, milled (out of .250 plate) cap strips for all Modell 5 wings. And not always do that on the Model B wings. But the plans are the same and the wings are normally identical. Mark

That hurts the potential entertainment of watching Nev build a Model 5