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From Piper Chieftan manual regarding engines by
xerj
Come across another thing that has puzzled me (big surprise).
Here's a transcript from the manual:
"Under full throttle operations (such as takeoff and climb) the engines of
the aircraft have been adjusted to provide 43 inches of manifold pressure at
seal level and standard temperature. It is...
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December 4th 05 01:24 AM
by xerj
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Shockwave formation on the wing. Is this diagram correct? by
xerj
On this page, there's an animated diagram (aptly done in shockwave) about
normal shockwave formations:-
http://selair.selkirk.bc.ca/aerodynamics1/High-Speed/Page2c.html
Something confuses me though. As diagrammed, the red pressure wave at the
rear has a low frequency at the front and a high...
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Future of GA piston fuel? by
xerj
If you had to do a bit of crystal ball gazing, what do you think the engines
of the GA fleet will be drinking in 10-15 years time?
The same avgas as today, just much more expensive?
Jet-A in diesel engines?
Something else?
( 1 2)
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Follow up to monster thread below re IAS and TAS and power required... by
xerj
Gettin' a bit confused here. (nothing new in that)
In the big sprawling thread I started down below, there's been a couple of
themes that have come up.
One is that I am pretty sure that for the same IAS (not TAS) at a higher
altitude, more power is required. However, one contributor to the...
( 1 2)
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February 5th 07 10:45 PM
by Al G
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January 29th 07 01:08 PM
by Tony
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A question I'm embarrased to ask - earth's spin by
xerj
I was talking about Coriolis effect with someone and he asked me about
planes against or with the earth's spin of around 1000mph at the equator. He
asked why this didn't benefit east to west plane travel timewise and hurt
west to east. I couldn't give him a straight answer, and felt like an...
( 1 2 3 ... Last Page)
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climb performance Jet vs Prop by
xerj
Do I have the following right?:-
Jet:-
Vx IAS stays the same as altitude gets higher.
Vy IAS reduces as altitude gets higher.
Both angle and rate of climb lessen as altitude increases.
Prop:-
Vx IAS increases as altitude gets higher.
Vy IAS reduces as altitude gets higher.
( 1 2)
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Rear stagnation point by
xerj
Yet again, this one has me puzzled.
I can visualise why the front stagnation point occurs, but other than saying
to myself "because it has to be at the trailing edge", I'm not grasping why
the rear stagnation point happens.
Can anyone elaborate? Most of the texts I find in searching basically...
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having a "blonde moment" when it comes to gyro procession and props by
xerj
Pitching a clockwise spinning (seen from the cockpit) prop forward will
result in a yaw to the left, pitching it up will result in a right yaw.
Correct so far?
However, why does a yaw to the right cause a pitch up, and a yaw to the left
cause a pitch down? I thought it would be the other way,...
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June 22nd 04 01:48 PM
by RT
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Propeller thrust question by
xerj
Thrust from a propeller drops as speed increases to a theoretical zero. When
this happens, what is providing the thrust to overcome drag? The forward
momentum of the aircraft?
If so, is it a case of the speed very slightly and imperceptibly dipping
below the zero thrust speed, getting a little...
( 1 2)
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November 25th 05 03:12 AM
by Dave S
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Anyone flown with an AoA indicator? by
xerj
Was reading an article in an Australian mag about an LED based AoA indicator
in a homebuilt. The author stated that in many ways it "replaced" the AI for
him.
Anyone have experience with them?
( 1 2)
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'nuther question: highest TAS... by
xerj
.... for a normally aspirated piston occurs at sea level and full power, but
for a turbonormalised engine it will be at critical altitude, right?
Thanks in advance.
( 1 2)
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October 19th 05 02:00 PM
by xerj
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Power setting table and best economy/best power... by
xerj
When a power setting table shows a "best economy" and "best power" setting
for a given power level (say 75%) using a given MP and RPM this is just a
starting point, right?
Once the MP and RPM has been set and the leaning done, the actual power
settings would be more like 78% for best power, and...
( 1 2 3)
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Fuel flow and leaning this time by
xerj
Yet another question.
Say you're at altitude and it's time to lean the constant speed engine(s).
You pull back on the mixture control, the EGT starts to go up. The engine
"sounds" more powerful as you do this. The prop might speed up momentarily
until the governor does its stuff and keeps it at...
( 1 2)
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Another thing I'm puzzled about: this time power settings and altitude. by
xerj
OK. These numbers are based on an extract from a power setting table for a
Lycoming 180HP :-
For 55% rated power with a FF of 7.4G/h at SL with an RPM of 2100, the MP
is 20.9.
For 55% rated power with a FF of 7.4G/h at 12,000 ft PA, again with an RPM
of 2100, the MP is 18.2.
I understand (and...
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practical best range application? by
xerj
I understand the theory vis a vis lowest L/D TAS and the power
available/power required chart, but let's say you're in flight in a normally
aspirated prop plane, your destination is blown up, your alternate is
unservicable for some reason or other and you need to stretch the fuel you
have the...
( 1 2)
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can't quite grasp the "power available" curve by
xerj
I understand the "power required" curve as plotted against velocity, but the
concept of "power available" plotted against velocity is escaping me.
How is this curve derived? And why is it "curved"?
Thanks in advance.
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September 12th 04 12:33 PM
by xerj
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resetting mixture by
xerj
Generally speaking, when making power changes in the cruise once leaned, do
you just adjust your throttle and/or RPM and THEN adjust mixture? I imagine
you wouldn't push mixture to full rich before making power changes at
altitude. Is this the case?
Further question: when going from, say, 24...
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