Interesting R22 question..

[gilabender]

My friend had this question asked to him on his CFI checkride but didn't give me the answer. Here's the question:

Why is the IGE in the Beta and Beta II different but the OGE is the same at max gross weight and standard day if the Beta II has more power?

I really don't wanna call Franky at the factory but I just might have to. Happy New Year to all.

[LongTailRotor]

In English please!!!!

Happy New Year!

LongtailRotor.

[gilabender]

IGE (in-ground effect) also known as hovering close to the ground. OGE (outta-ground effect) also known as a high hover. Any more clarifications??

[NGPogue]

I'll take a shot at it... If you look at the POH, the IGE charts are done at full throttle so the difference in horsepower between the O-320 and O-360 is obvious, the OGE charts were done a takeoff manifold pressure which equates to 131 HP with either engine, hence the same level in performance.

[kiwi chick]

How could a helicopter pilot not know what IGE and OGE is?


Or.... Iggy & Oggy as it is affectionately known in my wee neck of the woods.

[gilabender]

Yeah it does say takeoff power. But it also says "or full throttle at 104%RPM". What would the difference be?

[NGPogue]

As your density altitude increases you use more throttle for the same horsepower. Eventually you get to full throttle. With the O-320 you would expect to run out of throttle at a lower density altitude than with the O-360.

[philipnz]

This may contain some relevant information, i just happened to see it one day
http://www.caa.govt.nz/Publications/...g_Work_R22.pdf

[rockpecker]

kiwi chick

How could a helicopter pilot not know what IGE and OGE is?

Sipping one too many toxic beverage, in celebration of another complete solar orbit of the earth, might have softened the noodle just a tad too much. In his defense, take a look at where Long Tail Rotor lives - "Far Far Away" - perhaps the characters in Shrek know iggy and oggy by different names. Wonder what iggy and oggy would be for a pink dragon...