Gyroblade purchase

Sanko26

Newbie
Joined
Nov 24, 2019
Messages
38
Location
Hungary
I found a blade manufacturer, who offers blade for good price in Europe. I want to ask You guys,if these blade are good for a Bensen B8M or not. Blade: 3500 mm, 180 mm cord, 8H12 profile, 6082 aluminium extrudation. Please give me advice!
 
The hub bar length also must be taken into account if they supply that with the blades. The hub bar would have to be quite short because the blades are over 11'-5" each (3500mm). I don't know where the measurement was taken at the root, but 2X = ~23'. Going over 24' tip-to-tip is usually not recommended but without knowing the manufacturer makes it difficult for the more experienced folks here to offer a recommendation.
 
The hub bar length also must be taken into account if they supply that with the blades. The hub bar would have to be quite short because the blades are over 11'-5" each (3500mm). I don't know where the measurement was taken at the root, but 2X = ~23'. Going over 24' tip-to-tip is usually not recommended but without knowing the manufacturer makes it difficult for the more experienced folks here to offer a recommendation.
They also offer hub assembly, but I think I do it myself. It's a kind of "Humlan" rotorhead,what they offer but I don't know this type. I can ask them if they can offer a shorter blade,but I 'm 242 lbs and want to carry 8 gallon fuel. Don't You think that for bigger weight a bigger rotorblade set is needed? Just to keep the normal disc load.
 
So can any one give me advices concerning to this question?
Without naming the manufacturer it would be impossible to tell you if those blades would work on a Bensen B-8M.

Because most Bensen B-8Ms are different than the plans; without pictures of the aircraft there is no way to tell.

Bensen B-8Ms were designed for very light somewhat inefficient blades.

Some had inefficient wooden blades with a nose weight.

It is hard to know how a b-8M would work with heavier, more efficient blades.

The rotor head used is also going to make a difference.

A Bensen B-8M did not have eight gallons of gas.

A Bensen B-8M was typically powered by a McCulloch 4318.

Is this the engine yours is using?

This all affects how the gyroplane interfaces with the rotor blades.

I won’t be able to help you because I have had zero experience with any European gyroplane blade on a Bensen B-8M.

I am explaining this so you don’t feel ignored.

You are asking a difficult question without enough information to very few people who have had experience with modern European blades on a Bensen B-8M.

The safe thing to do is find some Bensen blades and build your aircraft to the factory specifications.

Is there someone near you who can train you in a Bensen B-8M?

Many Bensens were destroyed and many pilots were killed because training was not available.
 
[
Without naming the manufacturer it would be impossible to tell you if those blades would work on a Bensen B-8M.

Because most Bensen B-8Ms are different than the plans; without pictures of the aircraft there is no way to tell.

Bensen B-8Ms were designed for very light somewhat inefficient blades.

Some had inefficient wooden blades with a nose weight.

It is hard to know how a b-8M would work with heavier, more efficient blades.

The rotor head used is also going to make a difference.

A Bensen B-8M did not have eight gallons of gas.

A Bensen B-8M was typically powered by a McCulloch 4318.

Is this the engine yours is using?

This all affects how the gyroplane interfaces with the rotor blades.

I won’t be able to help you because I have had zero experience with any European gyroplane blade on a Bensen B-8M.

I am explaining this so you don’t feel ignored.

You are asking a difficult question without enough information to very few people who have had experience with modern European blades on a Bensen B-8M.

The safe thing to do is find some Bensen blades and build your aircraft to the factory specifications.

Is there someone near you who can train you in a Bensen B-8M?

Many Bensens were destroyed and many pilots were killed because training was not available.
As there are just composite "space shuttles" here in Hungary there is no training here for Bensen. No McCulloch engine here in Hungary, I plan to use Rotax 503 or 582. I try to get more info about the blades and after get back to you.
 
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As there are just composite "space shuttles" here in Hungary there is no training here for Bensen. No McCulloch engine here in Hungary, I plan to use Rotax 503 or 582. I try to get more info about the blades and after get back to you.

We learned a lot about modifying Bensen B-8Ms with a lot of bent metal.

We built gyroplanes with high thrust lines in relation to the center of gravity to take advantage of the larger prop possible with the geared Rotax engine that had some dangerous flight characteristics.

I hope you will spend some time studying this process because life is too short to make all the mistakes yourself.

Most Bensen derivatives fly very differently than any of the more recently designed gyroplanes despite the similarities.

I hope you will become proficient in a two place before you attempt to transition into a Bensen derivative and find a flight instructor who understands the process.
 
When you write "Humlan" (Swedish for Bumble Bee), I think of the old Swedish-built single seater.

And I know the swedes some years ago still kept a number of profiles and blades.

So it must be those people you've found. I do hope the 6082 has been heat treated to at least T6....

Please take lessons, so you are at least proficient in the modern gyro type.

A small single seater is much more sensitive and squirrelly - so I've read. Dangerous reading those "Just Do It!" t-shirts...

Cheers
Erik
 
When you write "Humlan" (Swedish for Bumble Bee), I think of the old Swedish-built single seater.

And I know the swedes some years ago still kept a number of profiles and blades.

So it must be those people you've found. I do hope the 6082 has been heat treated to at least T6....

Please take lessons, so you are at least proficient in the modern gyro type.

A small single seater is much more sensitive and squirrelly - so I've read. Dangerous reading those "Just Do It!" t-shirts...

Cheers
Erik
Thank you!
 
Flown the B8 with various blades. 22’ RotorHawks, 22' and 23' Rotordynes, 22’ McCutchens.

All flew slightly differently, but liked them all.

The MCCuthens were the smoothest, but the gyro did seem a bit less ’nimble’ with those ones.

The B8 seemed a bit less stable than the Cricket, Merlin, Hornet and LA-8, which I liked, but possibly because it was more manoeuvrable, though that is not necessarily a good thing for a beginner. Having learned on that from the start that was OK for me but take care as it is sensitive on the stick.

When you can balance it perfectly for repeated runs down the runway, then take it into the air.

Started with a 503 and a 52'' three blade IVO with a standard 5 gall tank. Performance sucked and could not get much above 500’ in the circuit. I was 200lbs and temps were cool at 700’agl. Changed to a 532, and a 4 blade 52’’ Arplast...world of difference. Annoying 532 characteristic power surge as the throttle advances which caught me out initially, but after that didn’t notice.

Preferred the 23’ blades to the 22’.
 
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Flown the B8 with various blades. 22’ RotorHawks, 22' and 23' Rotordynes, 22’ McCutchens.

All flew slightly differently, but liked them all.

The MCCuthens were the smoothest, but the gyro did seem a bit less ’nimble’ with those ones.

The B8 seemed a bit less stable than the Cricket, Merlin, Hornet and LA-8, which I liked, but possibly because it was more manoeuvrable, though that is not necessarily a good thing for a beginner. Having learned on that from the start that was OK for me but take care as it is sensitive on the stick.

When you can balance it perfectly for repeated runs down the runway, then take it into the air.

Started with a 503 and a 52'' three blade IVO with a standard 5 gall tank. Performance sucked and could not get much above 500’ in the circuit. I was 200lbs and temps were cool at 700’agl. Changed to a 532, and a 4 blade 52’’ Arplast...world of difference. Annoying 532 characteristic power surge as the throttle advances which caught me out initially, but after that didn’t notice.

Preferred the 23’ blades to the 22’.
Thank U for these suggestions! That's what I waited for! Althought it is nice from the other guys here to worry about me, but collecting information not dangerous yet. I graduated as a helicopter technician I have been serving in the Air Force for 17 years as a fighter plane technician, I have some hundreds hours on paratrike, I learned "human factor" and the most important I have three children and a beautiful wife. I write these facts for you just to see I know what I am doing. And I know the gyrocopter is totally different from the flying machines I tried so far, that's why I try to collect info as much as possible before I start anything.
 
Good attitude Sanko, take it steadily, be safe and enjoy.

If you want I can send you some notes for converting to the single seater, after lessons in a two seater which may be of assistance, just Private Message me your email. Two seater time is to my mind pretty essential.

In the UK we do have a syllabus for single seat PPL, it can be found here. It may give you an idea on how to proceed. Look for appendix B on page 53.

( A huge mistake to my mind in this syllabus, which I did have input into, was only allowing 2 hours of wheel balancing to count towards the licence. I felt 5 would have been better. If you did not need 5 so much the better, if you need more than that, yes should be on you.) Some people can balance almost perfect very quickly, some take much longer. You should not get airborne unless you can do successive runs... without going back and forwards from nose wheel to tail wheel, which is an indication of over-controlling.


With regard to blades, I am looking forward to being able to try the new Razor Blades being made in the US which will come with the single seat under way.
 
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