Hawker 800XP Stick Shaker test in Flight
 

Hi everyone,
I am interested on knowing if anyone has ever done a flight test on the Hawker 800 series after a 48 Months maintenance inspection which includes a stick shaker test in flight. Has anyone ever encounter any adverse flight conditions while doing the same Stick Shaker test on any other Jet?
Thanks.

You are talking about the test anytime the leading edges are removed?
I've done quite a few on both 800's and 700's and 1A's.
Follow the maintenance manual to the letter. Do NOT do like Ratheon and lead up to this test with A/P on and check that it pops off when stick shaker activates.
The successfull parameters of this test are fairly vague, If you end up right side up it seems they consider it OK.
Make sure there is no ice on the leading edge (avoid clouds, day,VFR) allow no one in the back, and it wouldn't hurt to make sure the toilet is empty.
After all these cautions, MOST of these were pretty benign.
We only had one 700 that would roll 90 degrees + to the right every time,
got your full attention the first time, then you knew what to expect.
Dave

Now, by no means do I have any jet experience (CRJ simulator course is all I've done), but are hawker's THAT bad? Considering that going to the shaker isn't the full stall, the 90 degree wing drop sounds like you guys take it farther than the shaker. So, for clarification, once you get to the shaker on a hawker, there's a dramatic wing drop? If that's the case, shouldn't the shaker be set to activate a few knots faster, so you have warning before the wing stalls? Thanks for the info.

What they are actually looking for is a stall. They want to see if having the leading edge off changes that margin between shaker and stall. Lear 25 in the hangar next to us hit a bird and needed a new leading edge. Lear brought their own pilots in to test fly, they said that one was real exciting.
Dave

Performed these tests last summer, really a non-event if your properly prepared. There's a graph in the AFM that will chart when the stall warning and identification are suppose to activate. Also there are procedures. Just review the material and follow the book. It's actually kinda hard to stall this aircraft, but it can be done.

Very interesting. So you fly (and stall) the plane with the leading edge removed? Anyone have any pics?

NO,NO,NO. After the leading edge has been off and has been put back on.
I hope you're kidding.:)

Pretty much all swept wing a/c have nasty stall habits.....hence the stick shakers, pushers, etc.

Makes much more sense... Unfortunately I wasn't kidding, but I did have a few drinks and was ready to believe anything! :cool:

Still interesting that the stall changes much with the same leading edge design. Learn something new everyday, I tell ya!

When you take the leading edge off a plane and later re-install it, just a few hundredths of an inch difference in alignment could make an aerodynamic stall go from predictably benign to a complete roller-coaster ride.

Be carefull doing these flights. Make sure that the gap sealer on the leading edge is VERY smooth and does not stick up into the airflow at all. Ensure that the stall triggers are rigged correctly too, to avoid any wing drop. I would make sure that someone who is Stall Check Qual'd perform the check, you had better know how to recover in the event of something bad.

I'm one for bringing the mechanic that worked on these things with me, so that way you get insurance that if they felt they did a good job, they'll fly, but also if something isn't quite right, they can see it for themselves.

Maybe I'm crazy, but I love doing stalls, and would at least like the experience of what happens in those planes. I fly/teach in TBM's, and it's not terrible. I do like to load the new pilots up so they can see the good and bad characteristics for themselves.

My understanding is that on test flights like these, only the required crew is allowed on board.

Joe

A mechanic can be a required crew member for diagnostic purposes.

I get calls to do test flights on Hawkers after maintenance from operators not comfortable doing them. The old adage "If you've seen one Hawker, you've seen one Hawker" holds true. I've had some wing drops (not 90 deg) and a few interesting rides, but if properly re-rigged, it stalls a lot like like a king air. I've taken the plane all the way to stall, and if you are prepared, it's not that big of a deal.

Interestingly enough, Simuflite uses one of their Hawker sims to conduct full stall training for pilots who will go on to do the test flights. Not sure if I buy the idea of using the simulator...but....