Garrett 900hp Conversion - C208 Amphib

[DareDevil]

Just in the process of getting the aircraft fitted for the garrett 900. Im looking for any experienced drivers input....operating procedures, advice, information, handling differences, dangers, high altitude performance, etc.....pretty much whatever ya have I'd like to hear it.

Aircraft will be ready in a few weeks and would like to get the professionals opinion on this aircraft.

thanks

[phillyfan]

The prop spins the other way and the tiny tail can barely hold her straight. You'll have it trimed all the way to the left and the pedal right to the floor to keep it straight. Any crosswind from the right and it can at times be too much.

[1000 HP]

Sounds like fun

[Colonel Sanders]

Is it insanely loud on the ground? Do ground crew run away when you taxi in?

If it makes half as much noise as moo-two, it's going to be painful.

[CamAero]

Garretts are awesome, tough, reliable, maintainable engines. In many regards, I think they provide better value than the PT-6.

[trey kule]

You'll have it trimed all the way to the left and the pedal right to the floor to keep it straight. Any crosswind from the right and it can at times be too much.

That is very odd. We used to fly with skiis and wheels off clean ice. Windcocking and torque were definite factors..But... There is a bit of technique, I think, that will solve that problem, particulairly with a nosewheel on a normal surface.

[1000 HP]

Philly's is on floats

[trey kule]

Ah, well that makes a bit of difference, but not all that much unless you are departing from extemely narrow bodies of water with crosswinds...just means a bit longer take off run. It still is a bit confusing to me that the extra horsepower can make a plane uncontrollable or need full rudder trim, but as I have never flown a garret caravan I will defer to the experts who have flown it.

[Capt. Chaos]

We have the Aerotwin Garrett mod on a amphib (850hp) and a grand (950hp). Aerotwin installs the engine canted down and to the left. One of our pilots who as also flown the Texas mod said it makes a huge difference. With the Aerotwin the rudder trim left around neutral. Does the Texas conversion have the SRL, NTS with auto ignition and fuel pump?

[DHCdriver]

I hear the speed and performance are top notch, but nobody talks about the off dock work such as dropping off hunters and fisherman on the side of a rock. I have never flown a Garrett on a float equipped 208 so I can't comment. My old buddy from my float days has a few complaints so I was wondering if he's just old and crabby or other guys have some issues with my scenario. DHC

[SuperchargedRS]

Very loud on the ground (point your nose away from anyone you dont want to go deft due to exposed front compressor), it's quieter in the air due to the lower prop RPM, the NTS is a pain in the ass for rapid descents, be sure to spin up the prop about 20 blades before start and after shutdown, you will want full left rudder trim for take off, on landing about neutral works great, for high angle climbs watch for cracks on the left inner flap area, enjoy the simplicity of the TTL & SRL, but be sure to watch the torque (presuming it may fail), it's single stage so dont let anyone turn the prop backwards in the hangar.

Great conversion, enjoy!

[nortont]

Do they do any tail or trim mods on the Caravan (short or long body) with all the extra power and torque ??

[rigpiggy]

it's single stage so don't let anyone turn the prop backwards in the hangar.

what do you mean single stage? The spinning backwards thing is due to brushes in the start/gen

[CamAero]

He meant fixed-shaft.

And that's right - it can damage the S.G. brushes if turned backwards.

CA

[longjon]

Why the 20 blades on a cold engine? Can you explain to me the reason for the prop turning on a shut down hot engine?

[Just another canuck]

Why the 20 blades on a cold engine? Can you explain to me the reason for the prop turning on a shut down hot engine?

Cooling effect... it SHOULD be done on every Garrett after every shutdown. Of course, we all get a little lazy sometimes and you always run the risk of breaking the paddle and ending up in the drink on a floatplane.

It should also be rotated prior to every start-up, to confirm it hasn't seized up on you. It just needs to be turned... 20 blades isn't necessary.

[DareDevil]

we have just started operations with the garrett and the performance is top notch! much better then the stock van on amphibs. Problem we are having is the new exhaust stack is actually burning the belly of the aircraft.....obviously an oversight by TT.

[Just another canuck]

I want to say there is a deflector you can get for the Otter... maybe. If there is, I would guess there's something similar for the Van.

You can wash the side of that thing and after one flight, she's black again. Almost seems pointless, although the boss wouldn't agree.

[JMACK]

Why the 20 blades on a cold engine? Can you explain to me the reason for the prop turning on a shut down hot engine?

Not really required.

On a hot engine to prevent shaft bow due to different cooling rates along shaft. If you don't spin it on shut down you could get it locked with a shaft bow but should go away when the entire unit cools. Not sure if a shaft bow will even hurt the thing if it is just going to sit for several hours. Would like an AME's opinion on that. I flew them on SWII and SWIII and J31 always felt like a hamster on a wheel spinning the prop, funny, always felt like a shit when the ground crew would get a blast of snow or grit when pulling them on the locks for shut down Single Red Line computer and Negative Torque Sensor make life easy and if it is NTSing at flight idle down hill just squeeze a little more jam in or get your tech to tune it a little.


I would love to try a 900HP C208 very cool!

Jim

[Just another canuck]

Not really required.

If you don't spin it on shut down you could get it locked with a shaft bow but should go away when the entire unit cools.

Key words... should go away. And if it doesn't and you try to start it, you just caused a lot more damage. That's the reason I was given anyway. Makes sense, no?