I was thinking of going out and testing what the “clean” glide ratio of my 185 on 3430’s is. I’m guessing pretty bad, like 5:1 or 6:1.

Anybody know the appropriate figure?

I’d be impressed with 6:1, but I suspect you’re in the ballpark. My Wilga 2000 on CAP 3000s was 4:1, draggier airframe mind you. Have a 185 these days, but still wheeled sadly, will definitely investigated once refloated.

https://backcountrypilot.org/forum/cess ... atio-22981

Looks like about 6-1/2:1 or so.

mtv wrote:

hotrod180 wrote:https://backcountrypilot.org/forum/cessna-185-floatplane-glide-ratio-22981

Looks like about 6-1/2:1 or so.

mtv wrote:

That diagram is for EDO 2960 floats. 3430s are a lot larger. Not sure how much that would affect glide ratio.

MTV

Hopefully you never have to find out

My 185 is on Wipline 3730 drag generators, has Flint tip tanks and VGs, so the "book answer" doesn't really address any of my performance characteristics. I've been planning to test the glide ratio, but don't feel like shock cooling the engine to find out how far it'll glide no-kidding power off. Guess I ought to go fly it, work the cylinder head temps down in a good location and test it for a few thousand feet.

This is just my opinion, not the way things should be, but I wouldn’t want to own and fly an aircraft I haven’t landed power at idle from different altitudes many times until it became routine. The beauty of owning it is you get to play with it as you see fit. Shock cooling isn’t a big concern in my mind for the amount you’d be doing, and a small price to pay for getting a visual approximation of how it lands with the stove out.

Just putt at a modest power setting for a bit with the mixture rich on a temperate day before throttle to idle. All those training school engines survive hundreds of PFL circuits done with full power climbs, a short downwind, then idle descents. Our engines can survive a dozen on a temperate day treated gently, and the practice is cheap insurance given the stakes.

My Wilga on floats dropped at the same rate the helis at the day job do, and I found I had to carry 20 more knots into the flare to touch at the same speed without rushing things at the bottom. It was a surprise to learn I needed that much extra speed to make it comfortable, and I wouldn’t have known without trying it. It was a lot easier to come down at a higher airspeed, pull flap once the spot was made, then trade speed for height to a soft touch on the water.

You only figure these things out through trying them, and since the engine is running, you get the option to say ‘Nope’ and try something else.

Wheels or floats I really don't have a clue what the glide ratio of the Helio is power off. I never felt I needed a number, I sure won't be sitting in the cabin doing math trying to figure it out when the engine grenades itself. What I do know and what I find much more useful is that in a 20 degree bank, the wing tip points to the spot on the ground which is the furthest I can glide to on floats. I found the number in an old military training manual for the Helio. I rocked the wings when I got to cruise altitude a lot when I first learned that to give me a good visual reference on how far I could go. Sometimes when flying in places with few good options I still do a little wing rock to see if I should go higher to give more options.

I find that bit of information to be far more practical if you are power off departing a lake and trying to get it back down or onto another nearby lake. Or if you are at 5000 feet and something happens and you are trying to turn to the best option. Personally I think all light airplane glide information should be disseminated in such a useful manner. Though I guess someone good with geometry could back calculate a glide ratio from a bank angle visual intercept or vice versa.

I guess you want to know if you'll reach that lake. Lots of variables -weight, wind - and what to add /subtract. Lost an engine on a Beaver at 6000', had a lot of time on my hands figuring things out. Was over land but made it to open water where a passing boat towed me in.

Helicopters drop like rocks but you can increase range by speeding up and pulling the rotor rpm way down. 47 I'm flying now comes down at a leisurely 1500'/m.

I can attest to the helicopter engine failures, had a Rolls turbine decide to remove itself from service below a thousand feet a few years ago.

You’re on the ground and winding down when you get time to think about it. Floatplanes are rather leisurely and relaxed in comparison.