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Re: Amphibs- SS or Highlander

PostPosted: Wed Feb 04, 2015 9:01 am
by Dave Krall CFII SEL SES
Early test flights of the Highlander on Full Lotus 1650s, when the engine was turning the 3 blade Warpdrive over 6000 RPMs like it should, yielded water slides around 10 seconds before liftoff, with about 500 pounds of one pilot, survival gear, and fuel aboard. The FL floats cathedral bows add lots of lift, especially in ground effect, much more than deep V hulls. Sometimes I swear there was no step at all. There were problems with turbo waste gate inconsistencies that caused much performance fluctuation because of that simple problem, which just needed more room ground out for the waste gate to swing fully. Never even really got full power most likely.

The new redone engine engine is running but needs a new mechanic capable of state of the art engine mechanics including electronic turbo push button scramble boost. I'm just not into actually doing mechanics that much so I'm interviewing auto mechanics that want to fly, since I can give them most any rating worth having. Conventional airplane mechanics typically don't have what it takes to care for this Suzuki auto conversion originally from Raven Redrives, his products giving great performance for over 15 years.

For those wanting extra lift, especially on a seaplane for takeoff in high DA, it is easy to put an airfoil between the floats, using an adequately strong front spreader as the longeron. The Highlander airfoil would be perfect for this, easy and light, especially with carbon fiber. This would give about 10% more wing area, depending on installation, and if extended laterally beyond the floats, much more area available.

Re: Amphibs- SS or Highlander

PostPosted: Wed Feb 04, 2015 6:25 pm
by Jack L

I contacted the guy (Pierre Girard) that makes the floats on the picture of the Savage Cub that I posted to ask him some questions. They are copies of Wipaire floats and he makes 1350s, 1400s and 1500s. The weight of the 1400 amphibs are approximately 260 lbs which are heavier than Zenairs but he says that you can cut that down by 15 lbs if you leave out the primer... not a good idea though. The total cost of the amphibs installed on aircraft is approximately $23,300 CDN which converted to USD is currently $18,536. Not a bad price considering that he does all of the work.

Since I started building my Zenairs I have been seriously thinking about selling them and going with a set of Pierre's 1400 straight floats. The straight floats weigh 140 lbs. I have to give this some more thought.


Re: Amphibs- SS or Highlander

PostPosted: Thu Feb 05, 2015 10:05 pm
by av8rps

Thanks for researching those floats. If his floats are the same as my CZ 1300 amphibs (like they look they are) he is offering one heck of a deal as I paid more than his price for a nice USED set. And frankly, was happy to have found them.

I'd hate to see you give up on your Zenairs as I think they are a nice light, good performing float. But I too like my CZ / Wipaire copies. So I can understand.


Re: Amphibs- SS or Highlander

PostPosted: Thu Feb 05, 2015 11:05 pm
by av8rps
I forgot to mention, that 15 lbs for primer sounds very heavy. So if it were me I wouldn't bother unless I planned on flying saltwater regularly. A buddy of mine has been flying his unprimed Zenairs since 1984 in brakish water and they still look like new (even though the 4130 tubing in his Avid rusted through).

The other thing I wanted to remind you is that if you decide to buy new floats, make sure he can supply you with freshwater displacement numbers on each size so you can size properly. My 1300's will easily float 1500 lbs, and if you read FAR 23-751 and do the math, you'll see the 1300s make sense for those numbers. So if his floats are sized similarly, you might want to consider going down from a 1400 to the 1300. I'd be happy to measure mine if you need that for comparison.

So many people wrongly describe how to size floats, and that is only made worse when manufacturers decide to identify their float sizes based on what gross weight aircraft they will fly, rather than their actual fresh water displacement. And frankly, I just wish they could all agree to doing it one way so this wasn't so confusing.