Piper Seneca Stall Warning
Thread Starter
Joined: Jan 2005
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From: essex uk
Why does the Seneca have two stall warning sensors on the leading edge of the same wing, and why does one of the sensors become inop when you select 25 or 40 flap.
Thanks
Thanks

Joined: Jul 2003
Posts: 1,092
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From: uk
And why are the Piper Seminole stall warners disconnected on the ground so that you can't test em?
Think lowering the later stages of flap on the Seneca alters the relative airflow making the one stall warner useless. Look carefully at the stall warner vane, they are positioned at slightly different angles.
Probably suggests why the Seneca seems to stall at full flap on landing, crashing down weakening the nose drag link on the nose leg that seems to fail a lot.
Think lowering the later stages of flap on the Seneca alters the relative airflow making the one stall warner useless. Look carefully at the stall warner vane, they are positioned at slightly different angles.
Probably suggests why the Seneca seems to stall at full flap on landing, crashing down weakening the nose drag link on the nose leg that seems to fail a lot.
Last edited by BigEndBob; 21st April 2007 at 21:11.
Joined: Jul 2004
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From: UK
When you select flap on the Seneca (or indeed almost any A/c), you alter the characteristics of the wing (chord, relative AoA etc), and hence the stall characteristics. Therefore you have a stall warner designed purely for selection of flap, and the different characteristics this produces, and because of the different relative AoA the warner is positioned on a slightly different section of the leading edge.
Fleet Manager

Joined: Apr 2001
Aviation Qualifications: ATPL
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From: various places .....
.. or, like with any aircraft .. make it do what you require ... I don't have much time on the Sneak but can't recall any real difficulty with landing .. maybe that is just a reflection on my "close eyes at 50ft" technique ..
Joined: Nov 2002
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From: the pub
Whilst we're on the subject, does anyone have any tips on how to produce anything other than a controlled crash onto the threshold from this delightful machine??
My best arrivals were,as Big End Bob says, with just 2nd flap selected.
Joined: Apr 2005
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From: Dry bar
A tiny fraction of power just prior to touch down could sometimes soften the blow. The seneca is a real handful once she starts to porpoise I seem to remember.
Think the stall warning vanes are isolated by squat switches on the ground I think?
Think the stall warning vanes are isolated by squat switches on the ground I think?
Joined: May 2002
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From: Canada
BigEndBob;
Are they heated vanes? If so they would not be powered on the ground.
I don't see any point in frequently testing them on the ground other than to verify that the wiring is intact and the horn is functional (usually the same horn is used for the gear warning). The maintenance dept. likely does that type of check during the annual inspection (with the aircraft on jacks). They are not very accurate devices. Testing via an actual stall would be a better indication of correct function.
Are they heated vanes? If so they would not be powered on the ground.
I don't see any point in frequently testing them on the ground other than to verify that the wiring is intact and the horn is functional (usually the same horn is used for the gear warning). The maintenance dept. likely does that type of check during the annual inspection (with the aircraft on jacks). They are not very accurate devices. Testing via an actual stall would be a better indication of correct function.
Last edited by Tree; 22nd April 2007 at 19:48.
Joined: Jan 2005
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From: Grand Com f'Ort
Don't use power - it nadgers your performance.
DO close the throttles at about 20ft, put both hands on the control column, and concentrate on an accurate flare, which may take a moment or two.
No problem...
DO close the throttles at about 20ft, put both hands on the control column, and concentrate on an accurate flare, which may take a moment or two.
No problem...




