Redundant mast

jvan777

Newbie
Joined
Jun 4, 2016
Messages
23
Location
Jackson,Mi
When someone talks about upgrading a Bensen style Gyro to a redundant mast, are they speaking of two 1x2 .125 wall tubes sandwiched vs a 2x2 mast? I am very new to gyros and appreciate any feedback. I have not purchased or started building a chassis at this time. I know there are much more advanced designs than the bensen but, I cant get past the nostalgic appeal of those machines. I have to believe there are many people who have enjoyed many trouble free hours in these machines despite their reputation as being dangerous. Plus I need to find a use for the 4318 Mac that I just purchased. Thank's : Justin.
 

Alan_Cheatham

Member
Joined
Nov 14, 2003
Messages
1,972
Location
Dallas, Texas
When someone talks about upgrading a Bensen style Gyro to a redundant mast, are they speaking of two 1x2 .125 wall tubes sandwiched vs a 2x2 mast?

Yes, two 1x2 .125 properly bonded together to form a 2x2 mast. The idea is if a crack does develop it becomes harder for the mast to fail given the redundancy.

Methods for bonding the aluminum tubes together are in other threads on the forum so you may want to search them out.

.
 

SMOF

Newbie
Joined
May 2, 2016
Messages
57
Location
Elko NV
Back in the 1970s, guys were changing out the masts on already-flying gyros to get the redundant mast. I would consider it a must-do, especially if you weigh more than the FAA Standard 175-pound pilot. The added weight is negligible, the added strength is noticeable.

BTW, the Benson isn't particularly "dangerous," the rep is mostly from people who learned to fly them from the syllabus in the book (there weren't a lot of two-holer gyros), then tried to yank and bank while they were still inexperienced.
 

GyroCFI

Gold Supporter
Joined
Jun 24, 2008
Messages
872
Location
Petersburg, Illinois
Aircraft
Snobird Tandem Adventurer
Total Flight Time
3500
I know there are much more advanced designs than the bensen but, I cant get past the nostalgic appeal of those machines. I have to believe there are many people who have enjoyed many trouble free hours in these machines despite their reputation as being dangerous. Plus I need to find a use for the 4318 Mac that I just purchased. Thank's : Justin.

I loved my original Bensen type! Had a Rotax 503 Dual Carb and flew the heck out of that gyro! Mine had a redundant mast, but I don't think i bonded them together. Wish i still had it.
 

WaspAir

Supreme Allied Gyro CFI
Joined
Oct 21, 2006
Messages
5,000
Location
Colorado front range
Aircraft
Bell 47G-3B-1 / A&S 18A / Phoebus C, etc.
Total Flight Time
stopped caring at 1000
I have to believe there are many people who have enjoyed many trouble free hours in these machines despite their reputation as being dangerous. Plus I need to find a use for the 4318 Mac that I just purchased. Thank's : Justin.

"[M]any trouble free hours" and "Mac" in the same paragraph!
 

phantom

Newbie
Joined
Apr 1, 2009
Messages
1,415
Location
Eagle River
I have flown thousands of hours on single tube masts and on some machines I have tried a dual tube mast and had to go back to a single due to vibration problems, if a machine is properly designed the mast is mostly in tension, I have seen machines that have long head plates to balance a nose heavy condition, this will put a backward bending moment into the mast, you want your rotor head as close to being at the end of the mast as possible, if you are building from plans you should stick to what is called for by the designer.
Norm
 

scottessex

Sling-Wing Pilot
Joined
Nov 12, 2003
Messages
11,172
Location
central, ga
Aircraft
Dominator 582
Total Flight Time
200+
I just replaced my dominator mast with a single wall 2x2, hopefully it will get rid of the vibration I had.
 
Top