Harrier
 

How much power do you need for a plane to harrier? Would a 1/1 power weight ratio be enough?

Harrier
 

Harrier flight is usually flown at 1/4 to 1/3 throttle on most planes so power is not really a prerequisite for flying in a harrier. The vertical hover and torque rolling is the manuevers that require at least a 1.5 to one thrust to weight ratio.

Harrier
 

1 to 1 would not be enough. To really get the plane into a nice harrier you are almost totally hanging on the prop and the plane is just crawling down the runway, even in a gentle downwind. Also, you are constantly juggeling the throttle and sometimes you need to jerk the plane up FAST like after the engine coughs for a split second. It can be done on 1 to 1 but you'll have to be good and the engine and fuel delivery will have to run flawless.

Harrier
 

I think the two very different above responses may be due to very different planes? A smaller fun-fly type won't have a very efficient wing or tail surfaces so it may need more power for a harrier while a larger plane will be more efficient.

Regardless, 1:1 is more than enough to harrier. Think about it. Most harriers have a nose high attitude of say 30 to 45 degrees and a very slow forward speed. It should be intuitive that that the wing is providing a large portion of the lift, I'd say well over 50%, maybe even close to 90%. Harriers do not "hang" on the prop... you are flying the wing in a high drag bucket. The high AOA stalled wing will generate a lot of lift, it is just not very efficient, i.e. lots of drag. For the most part, you only need enough thrust to keep the tail surfaces flying so they can maintain the high AOA on the wing and of course you need to overcome the drag.

I fly harriers in my 35% at about 25% power. This works out to about 0.5:1. However, having a reserve of 2:1 is nice. While you can fly a harrier with low power, your only transition afterward is down or level flight. High thrust will let you transition to a hover, etc.

Cheers.

Harrier
 

It all depends on your plane , how heavy, how light the wing loading etc.

My Carden 40% Edge harriers just above idle.....


Josh

Harrier
 

Shoot,
My edge harriers just over half throttle. Still think I am underpowered...
RickP

Harrier
 

I guess my interpretation of the harrier is different. When I harrier the plane is at walking speed and probably 70degrees nose high, and 1/2 to 2/3 throttle. This is the .46 size funfly/PQHOR planes.

What is a harrier? How fast is the plane going?

Harrier
 

A harrier essentially is where the plane is moving forward while holding itself from stalling by using power.

70 degrees is whats known as High Alpha harrier.

Harrier
 

I have seen the Harrier airplane many times at shows and assumed the maneuver got its name from the real plane. During demos the jet would slowly "hover" down the runway and back, do turns etc. purely on brute thrust from the engines. I have been modeling that, with very slow high alpha "hovering" around the runway in straight passes, ovals, figure 8's etc.

I learned something new. Thanks

Harrier
 

In my book, a harrier is any forward flight (inverted/right side up) where the wing is flying at a AOA past the threshold of the stall, i.e. your in the high drag bucket part of the lift curve.

Throttle isn't used to prevent the wing from stalling... the wing is already stalled. Throttle is used to keep the stabs unstalled, i.e. flying so they can provide the needed down thrust required to keep the wing at a high AOA. Most aerobatic wings will probably stall at a AOA of 15 degrees. Now this is AOA, not attitude with respect to ground, but still, if your 30 degrees nose high and crawling along, I guarantee your wing is stalled.

Simple vector analysis should intuitively prove to most that the engine isn't providing much in the way of vertical thrust if your doing a 30-45 degree harrier at low throttle. If I harrrier at about 0.5:1 thrust/weight and I'm at a 45 degree angle, I'm only directing 0.25:1 thrust down... that means the wing is still responsible for 75% of the lift.

I'd consider a 70 degrees nose high attitude a hover, not a harrier, but that's me.

Cheers