Parking with flaps extended
 

Hello folks, a little question out of curiosity.

On Saturday I happened to notice several Citations parked on the Business Aviation apron at EDI, and one thing I spotted was that they were all parked with flaps extended. Also, I happened to be browsing through some Piper Tomahawk pictures on an aviation site when I noticed that several were parked again with their flaps extended.

This intrigued me, since at my club we always park with flaps up, and this also seems to be the norm on all Boeings and Scarebuses too.

Any particular reason why some aircraft are parked with flap down? :confused:

Can't comment on the biz jets but the PA38 and DR400 it is common practice to park with flaps down to stop people standing on the flap when entering and exiting the aircraft.

On the scarebus it is normal to leave the slats extended when the temperature reaches in excess of 30 degrees (no hope of that in EDI this year :\ ).

The reason being that the sensors that detect a wing bleed leak can get confused by the temp if the slats are shut and don't get any cooling air flow. Therefore it avoids nuisance ecam warnings in the cockpit.

It is standard practice for certain series of Citations to be parked with partial flaps to prevent strain on the flaps systems. It has been a long time since I flew a Citation, however, I'm sure there is a Citation pilot here that can explain the reason better than I.

Wobble2Plank

Is that Slats thingy in FCOM somewhere?

Look in FCOM 3 under SOP after landing.

On A300 we park with slats extended.

Reason, less wear cause we take off 99% slats only.

Hetfield, we used to do the same on long runways(BAH) but use 15/15 now.In fact I cannot think of anywhere we do this,but we do put them away at night!
Many years ago we had an aircraft damaged taxi-ing in on a contaminated surface across in the US.It damaged the flap mechanism.However somewhere during the telephone call to engineering this translated into slats!!The engineers turned up with a big spanner for the slats and the rest as they say is history!!

For 500 series citations (and others i am sure) walkarounds must be done with the flaps partially extended. I think there is a sight glass that cannot be seen with the flaps up.

I have never had any bleed leak warnings and always select flaps 0 for parking, we did however have a fuel truck hit one of our 321's recently and damage the trailing edge, aircraft was parked in Config 1. :ugh:

Thanks for the replies folks.

Smithy

3 or 4 years ago on the minibuses it was fairly common to get spurious but locked in ecam message of wing air bleed leak at >+30 c with slats up.
However most aircraft have since had this software glitch mod'ed out so its ok to leave the slats/flaps up in high temperatures now.

On the CRJ 100/200 we leave the flaps at 20 after landing, unless it's the last flight of the day then we bring them up. This reduces wear/tear on the flap drive system/FECU as well as allows us to check an AD that requires us to check and examine the position of the flaps before every takeoff.

The main problem I see with parking with the flaps extended is that it allows the actuation compontents to be exposed. The exposed compontents could be contaminated by moisture and dirt.

@tubby linton
 

Yeah, for night stops and when no flight crew on board we retract them as well.

I seem to remember from years ago that the flaps on the HS 125 would droop after being parked for some time, simply because there was no hydraulic pressure.

On early model 500 series the flaps were cable drive. Because of this they were only to be left up when in flight or else the cables stretched.

Most (maybe all? ) of the airliners have hydraulic flap system, so after been parked for a while with no hyd pressure, they start to drop.

they start to drop.

No Sir.

flaps extended
 

there are only 2 perfrctly good reasons for parking an aircraft with the flaps extended.
one - fatique as happend to us lately
two - hijack, for god's sake they didn't mistake us for it those days
if the maufacturer require it - somethings really wrong!!!
Three --- real major problem!!!