N13HP down?

[Curt]

Re: N13HP down?

Does the Fury-Sea Fury have any bad habits that can surprise a new to the airframe Pilot ??

[Wild Bill Kelso]

Re: N13HP down?

Does the Fury-Sea Fury have any bad habits that can surprise a new to the airframe Pilot ??

A prop going to flat pitch can take out the best of them.

[Ken Adkins]

Re: N13HP down?

I was thinking the same thing (flight characteristics of the Mustang vs. the Sea Fury). Bill, can you elaborate on the "flat pitch" issue?

[Wild Bill Kelso]

Re: N13HP down?

I was thinking the same thing (flight characteristics of the Mustang vs. the Sea Fury). Bill, can you elaborate on the "flat pitch" issue?

Speculation that is going around. The prop went to flat pitch.

[Arctic Cat]

Re: N13HP down?

Speculation that is going around. The prop went to flat pitch.

Not speculating just asking for clarification and understanding. When the prop goes to flat pitch on this type, it would be a prop governor issue correct. Loss of oil pressure to the prop allows the blades to go flat, causing an increase in rpm of the engine and you would have to pull power to keep it from overspeeding the engine. That along with the increased drag of the blades slows things down pretty qucik. Is this correct?

[Wild Bill Kelso]

Re: N13HP down?

Not speculating just asking for clarification and understanding. When the prop goes to flat pitch on this type, it would be a prop governor issue correct. Loss of oil pressure to the prop allows the blades to go flat, causing an increase in rpm of the engine and you would have to pull power to keep it from overspeeding the engine. That along with the increased drag of the blades slows things down pretty qucik. Is this correct?

Yes. Throw your car keys out the canopy and you will land in the same place they do.

[Ken Adkins]

Re: N13HP down?

That explains a lot (sadly). Thanks Bill.

[Curt]

Re: N13HP down?

My interest is in General flying characteristics for the Bird..

[ChrisMX105]

Re: N13HP down?

NTSB Preliminary has been released.

[IcePaq]

Re: N13HP down?

How flat does that prop go?

He had a positive climb rate at 3500rpm.

[Dudewanarace]

Re: N13HP down?

Although I don't know that number, I will venture a few thoughts.

One being that things usually work just fine till your past the end of the runway, then everything goes to hell. So I suspect even though it sounded wrong on the ground, the positive rate of climb mentioned, only got worse, turning negative it sounds like.

Another is making thrust at 0 airspeed is one thing, using the same angle to make thrust at some speed above stall is entirely different.

Imagine flying any airplane, just barely above stall, while it is running hundreds of rpm over red line.. Something you really can't reproduce outside of a run away prop. I feel the engine noise would make you have an overwhelming desire to continue flying, mistaking the pending stall. "All that rpm, all that power, surely this will fly" is probably what goes through your head. I can only hope if it happens to me I remember to not listen to myself and fly the airplane all the way to the ground.

Sad deal..

[First time Juke]

Re: N13HP down?

How many flying hours did he have on this kinda aircraft ?

[Magdrop]

Re: N13HP down?

I don't understand why the prop would go flatter than takeoff pitch? Does the hub have internal stops that can be set? I would understand if it was a reversible pitch prop.

[Dudewanarace]

Re: N13HP down?

But, takeoff is not a constant.

The only time I would expect the prop to remain at the pitch stop is just prior to movement on the takeoff roll. Even then, only briefly while power output is very low. The definition of constant speed is just that, constant rpm. The governor adjusts pitch to control the rpm given the power output. So, as soon as your moving and the power output increases, the blade takes a bigger bite to control the rpm. I'm trying to think of a different way to explain this...

Full forward on the prop lever does not mean the blade is on the pitch stop. Full forward on the lever means the governor will produce a blade angle to maintain the set rpm. (lever position) What this blade angle is defines the governor output to get the desired rpm.

Now, given more speed, the blade has to take a bigger bite to maintain rpm, so the governor pumps out more oil. Same goes for power output. Make a bunch of horsepower and the blade must also take a bigger bite, thus more governor output, thus you get the desired rpm. (lever position)

Take away oil pressure (with a non-counter weighted prop), or fail the governor, and you lose control of rpm. Then the only way to control rpm is with a huge reduction in power output, or an appropriate forward speed. Often that forward speed may be slower than you can fly..

Some of you may remember some prop overspeeds in the sport class over the last few years. Vicky Benzing lost the governor at the start and it zinged to the moon because of the high forward speed and high power output. (like shifting your 10 speed to 1st while peddling at 60 mph) She correctly, and instantly, pulled up and got the airplane to slow down under G, safely landing. (with a ruined prop/engine) I'm sure everyone remembers Kevin Eldredge in Relentless losing oil pressure, while hauling ass and making tons of power. Zing and kaboom! No time to react, and we all saw what happened.

Constant speed props are not connected to the lever in the cockpit. The lever connects to the governor that sets the blade angle to produce the desired rpm set by the lever in the cockpit. Make sense?

[First time Juke]

Re: N13HP down?

Speculation that is going around. The prop went to flat pitch.

I figure just adding more power would throw the plane inverted..if not experienced ?