Grove gear on a model 1

[dalords]

How much airframe modification is there to installing Grove Gear on a model 1? If you use the gear for a model 3 do you have to widen or move the gear mounts? think about putting some on my model 1.

[SkyPirate]

have you checked the complete set up weight for grove gear,..and which ever brakes and tires you plan on using? compared to stock gear weight ,..its heavier.
to install grove type gear on the earlier models you'd have to reinforce the area behind the front door post on the bottom longeron,..the area where the bottom front side of the door,..which will also add weight,..
I'd look into High WingLLC replacement gear ,..you use the same mounts already on the plane,..end up with a wider stance,..and a little more give,..without adding too much more weight or modifications


Chase

[SS7Flyer]

Skypirate I've been hearing about a lot of bent fuses from guys running the Highwing gear due to a geometry issue of the V on the Cabane strut. Does anybody have any real world knowledge of this? I know a few people who have considered running it but it's not worth it if they will destroy their fuse on a rough landing.

[tommg13780]

The net difference between grove and bungee gear is 19# according to my bathroom scales. Your useful load with the model 1 is probably around 400# with the bungee gear, now 381# with grove. With ten or so gallons fuel you now have effectively made the model 1 a single seat.

[HighWing]

Don't exactly know what to say here, but here goes. There are three versions of the "Bush Gear" out there (Maybe four if you consider the first guy that tried it with the Kitfox). Kitfox Aircraft makes a version, Airdale makes a version and we make a version. We have had two incidents. I don't know if this constitutes a "lot", but it is what it is. One was a fully loaded Model IV and the other was an admittedily poor landing in a Model III that not only tweaked the fuselage, but it destroyed the cabane. I have heard stories that the other two manufactures have had incidents as well and I know that the "First Guy" had incidents as well. I sincerely hope we have not been given credit for these.

Here is the issue. I have received inquiries about our "Bush Gear". I always make it very clear that our gear is designed as a cabane style spring gear. We don't use "Bush" in any of our documentation. Our gear was designed as a more stable replacement for the original bungee gear from the factory. And in that, it has proven very successful. Since the proliferation of all the videos of the wild landings on river banks and big rocks, there have been a greater number of pilots wanting to try that. I believe there is a perception that all that is necessary to become a bush pilot is having "Bush Gear" and big tires on your airplane.

It is true that with the longer gear legs and wider stance there are different forces placed on the fuselage. If your plans are to have a more stable gear for landing on pavement and grass any of the extended gear leg manufactures can fill that bill. And for that mission, I don't think any of the manufacturers have had any issues with their gear. If you want to land in the rough remote areas of the world, you might want to think about doing some retrofitting on a fuselage that was not designed to withstand those types of landing forces. Maybe a comment on that would be appropriate. A perfect landing wherever, is a perfect landing and any gear fuselage combination would be fine. A less than perfect landing? What or who is to blame for the results - think Ariana. I would be curious to see how the original bungee gear or the Grove gear would perform on sand bars or big rocks. (I am currently in the middle of helping a friend repair his fuselage after a hard landing with Grove gear.)

In short, if you are looking for a more stable gear designed for the vast majority of pilots and destinations, any of the spring gear types out there would work for you. If you are looking to be the next video sensation, you have seriously entered the world of experimental aviation.

[SkyPirate]

all that I can think to say in a reply is that the weakest part of any combination of tubing, springs, and tires is going to give,. in an other then normal operation,..anything outside of "normal" = flat unobstructed landing area,..when I say flat I mean in one plane,..it could be slanted ..tilted ..falling away,..up hill, down hill etc
at this point its PIC's decision..not the landing gears ,,to submit any type landing gear to the test :) ..wow just re read that..I should run for office ha ha

Chase

[FoxDB]

Well back to the original question, The Grove gear can not be used on a mod 1 as the fuse does not have the forward most lugs as the later models. And further more additional brace tubes were added to allow this loading.
As to the fuselage strength issue, I built my gear similar to the Highwing gear but added additional attach lugs for the cabane V. And I bent the fuselage on a hard landing. The lug placement for the Gear leg is directly under the longeron. This puts the compressive loads of the gear leg offset from the longeron and causes torsion loads to the longeron. When I repaired my fuse I took steps to deal with this. Not hard landings since so.. no report.

[SkyPirate]

something like this would help..if the image comes thru

[SkyPirate]

could do this at both front and rear mounting points but just a straight carry thru on rear

[SkyPirate]

doing the above keeps all structurally added strength as an exo skeletoral addition ,..no cutting and removing fabric
doing this you would be relieving some of the diagonal load pressure of having a wider stance,..the carry thru tube would be taking most of the load

[SkySteve]

Model I with Grove Grear on a very nice, smooth paved runway (yeah, right) or an island cow trail:

http://i237.photobucket.com/albums/ff12/KitfoxSteve/7F5599D6-067F-4A9B-8E34-65910B20045F-2747-0000029346848FB9.jpg

[SkyPirate]

being very close to the strut carry thru,..did you have to add much support around the lower longerons Steve? or was there enough " meat" there already?

Chase

[Dave F]

If you want to look on how ot make a tougher gear then look at what Highlander has done. Look at the video with the slats to see how you can hammer this gear. http://www.youtube.com/watch?v=5ccYFqY4Ymg

The guys making them now should be using the front float attach bracket as well making it a 50% improvment in gear strength as you know has 3 legs rather than 2. plus the weight is distributed over 3 attach points rather then 2 .
But remember the longerons are not strong enough to take a real beating especially the models 1 and 2 and 3

Guys were bending the 1/4 bolts and now using 5/16" diameter bolts.

The new highlander gear with the new suspension allows for I bet 10 to 16" of travel. the Cabane style cannot take this.

I have done some pretty radical flying in very rough terrain with stock gear. Model 4 though which I bet is 50 % plus stronger than the earlier thinner wall tubing.


Food for thought before you write off your plane using a gear that you only think might take a beating and it jus might but the "chain is only as strong as the weakest link".

[SkyPirate]

It's all experimental until you find something that doesnt leave you stranded with , options are working with what you have, and keep in mind, what your working with :)

[FoxDB]

Dave F,
When designing my gear for the Kitfox 1, I considered a 3 point attachment of the gear legs. My mod does not have the forward attach points. Although from what I understand the forward points Centerline is not inline with the other 2 attach points anyway. My hard landing was extremely hard yet the gear fared fine.
Dave