Embraer Rear Engine turboprop
08-17-2021, 04:24 PM
#31
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Originally Posted by hydrostream
PC-12 NGX sounds like it’s similar to the Q400. There’s a button to switch between RPM settings. That’s exactly what the “condition lever” on the Q does. There’s no fine adjustments, it just rests in detents and tells FADEC which setting you want: 1020 (NTOP/MTOP), 900 (MCL) or 850 (MCR), start/feather, or fuel off. They could have eliminated it entirely and just used buttons and it would have functioned the same, in fact there are buttons to do just that. One setting allows us to maintain 850rpm for landing even after the condition levers are moved back to 1020 (reduced NP setting). Power levers sit in a detent to command max power in the selected setting until you pull them out to adjust power.
I assumed the ATR was similar, is it not?
I assumed the ATR was similar, is it not?
08-19-2021, 12:13 AM
#32
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Originally Posted by SonicFlyer
Hey, I'm open minded and willing to learn. Teach me.
08-19-2021, 05:00 AM
#33
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Originally Posted by kevin18
Yaw moments have to do with lateral displacement from the center of the CG. Also, with greater displacement they use larger rudders to be able to control the yaw. Compare a 900 to a 175 and look at the difference in the rudder. It directly correlates with the placement of the engines as they’re pretty much the same engine.
08-19-2021, 10:01 AM
#36
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Originally Posted by kettlechips
... Which axis were you thinking?
08-19-2021, 11:16 AM
#37
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Originally Posted by SonicFlyer
My thought process went like: "If the engines are in the rear, then that means they are further away from the vertical axis, thus allowing for more yaw during a V1 cut... with a jet it doesn't matter so much but with a prop that's a lot more force to deal with"
But the rear displacement would only be effective arm for a force perpendicular to the longitudinal axis
08-19-2021, 11:20 AM
#38
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Originally Posted by SonicFlyer
My thought process went like: "If the engines are in the rear, then that means they are further away from the vertical axis, thus allowing for more yaw during a V1 cut... with a jet it doesn't matter so much but with a prop that's a lot more force to deal with"
Once yaw occurs you do get a little additional yaw force from the engine moving horizontally out from the CG as the tail swings. But you'd never notice that because the yaw also swings the v.stab out into the breeze at the same time.
08-22-2021, 07:10 PM
#39
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Back in the late 80's they were flying the CBA123 pusher, a 19 seat proof of concept... The aircraft was quite fast and quiet... Cost killed it for a 19 place aircraft... Take the concept and advances of 30 years and they may have a winner... Time will tell, they just don't need to over engineer the thing to keep the cost in line with the market... My 10 yen...
Cheers
Cheers
08-23-2021, 04:28 AM
#40
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Originally Posted by ZeroTT
A windmilling prop IS more force than an inop jet
But the rear displacement would only be effective arm for a force perpendicular to the longitudinal axis
But the rear displacement would only be effective arm for a force perpendicular to the longitudinal axis
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