Patrol Float Fitting Locations

[Steve W]

Float fitting mod as per News Letter December 2006 shows the location at station E. From the picture advertising the Seaplane Fuselage from the store, the fittings are at station D. Any discussion on this?

[Chris In Milwaukee]

Yes, I see the same thing on p.41 of the Bearhawk Patrol Book. The modifications from Bob are discussed there, and they are a welded-in tube at a cluster above Station E as you suggested.

That being said, however, the fittings in the Patrol Seaplane fuselage are not the same as the ones in the plans. The ones on the Patrol Seaplane look to be mounted on the bottom of the fuselage tube, and look to be more of an adaptation of a gear attach fitting. One of the 4-place builders has used the same type of fitting on his instead of the through-the-side mount that you see in the plans.

I'm sure Mark Goldberg can provide more detail, but the one you see on the seaplane are definitely different.

[Mark Goldberg]

The current float fittings for the rear float attach do look a lot like the landing gear attach fittings, and attached at station E-M. Mark

[Steve W]

I know it's been a while sense we discussed this but I looked at the seaplane fuselage again and the rear fittings are at station "D" not "E" as per the mods for float fittings unless I'm missing something. What I originally was getting at was why the change?? Was the original station "E" too far back for a clean attachment to the float?

[lsa140]

I'm curious about this as well. Where is the rear fitting, and at what station would the front float strut attach? The font gear attach (B) to station E is around 71". Station B to D is around 46". Cubs attach around 42" apart. Looks like attaching to D would put the rear strut angled slightly to the rear, and attaching at E would place the rear strut angled forward quite a bit. (when viewed from the side)

Looks like it is a mix on various designs on where the rear attach is placed. Some at the rear door post, and others farther aft at the next vertical fuselage support.

I drew up a set of 1450s under the LSA and posted it in my build thread: http://bearhawkforums.com/forum/bear...40-build/page2

[Steve W]

If you notice the second aircraft, Champ or Citabria, you will see 6 attachments to the fuselage from the floats. This is the strongest setup you could have. By looking at your mock up I think the attachment at station E should be OK. I was getting concerned that someone might have found that the rear station was too far back creating an unacceptable angle to the rear float attachment. If your mock up was close to the step of the floats being 2-3 inches behind the most used center of gravity then I'm not concerned. I don't have the numbers right at hand for the spreader bar spacing for larger floats such as 2000 EDO or Caps but I bet they would be greater than the ones shown in the mock up which would lessen the angle somewhat. I think you could use B or C for the front attachment but you would have to place the float in relation to the used C of G and the step. From what I see on the seaplane picture all landing gear and float fittings are all on the same flat plane which makes it a lot easier to make all the mounting hardware square. There is a minimal amount of twist when adjusting the 3-3.5* throat angle between the float tops and the level fuselage.

What really concerned me was that from my plans, station D is not very strong for a float attachment without some modifications. I have my fuselage completely welded and would not want to replace the vertical and lower horizontal tubes.
Thanks for the discussion

[lsa140]

The changes Bob incorporated into the Patrol plans from 271 and up (http://bearhawksafety.com) would add some strength to station D. I have no experience rigging floats, but visually comparing other aircraft's installations, the geometry of attaching the rear float strut to D or E (on the Patrol) looks doable. I would think that either location would need some type of strengthening when attaching floats, like shown on page 41 of the Patrol book.

On the LSA, I think station E would be too far aft.

[alaskabearhawk]

It's an apples to oranges comparison. The Bearhawk 4 place would take a longer/larger float (like in 2008 Beartracks) than the Patrol. That makes the fitting locations much different. Also, the gear mounts on the Patrol are farther forward by a few inches than the 4 place in relation to the cabin, making the geometry for the float struts different. I don't have Patrol plans, but just judging from the picture the distance from Station B to D in the Patrol is further than Station B to D in the 4-place. Also, it really depends on the float manufacturer, but Station D looks very doable. It actually looks like the preferred location to me.