|
PC-12 Nose-Down Attitude |
Post Reply 
|
| Author | |
sfaison 
New Member 
Joined: November-28-2008 Points: 2 |
 Post Options
 Thanks(0)
 Quote Reply
 Topic: PC-12 Nose-Down AttitudePosted: November-28-2008 at 5:33pm |
|
Hello. I have two questions regarding the attitude of the PC-12 at two different phases of flight.
1. During cruise, my PC12 has a slight nose down attitude, regardless of altitude. Did a flight yesterday at 9,000, and a flight today at FL250, both with about a 1-3 degree nose down pitch throughout cruise. Is this normal? I've seen vids on YouTube where the pitch is pretty close to 0 (never below), but not sure if the negatives are normalcy. My speed is reasonable - about 15-30 IAS less than maximum. If anyone knows how to determine proper cruise power for each flight, let me know. 2. The more tricky and important situation for me. On final, on my way down, let's say with flaps 15, I'll be doing about 100-110 IAS. However, the nose down attitude is about 5 degrees. Since I don't want to go any more with the pitch down, the G/S indicator drops and/or White Papi lights increase. Then with either 30-40 flaps and a speed of 80-90 IAS, it's even worse. So I'm wondering if anyone has any tips or corrections for the approach phase. Note: Using FS9 Any help is appreciated, Stephen Faison |
|
 |
|
|
folie
New Member
Joined: December-02-2005 Location: Netherlands Points: 38 |
Post Options
Thanks(0)
Quote Reply
Posted: December-07-2008 at 9:01am |
|
Stephen, To give you a simple answer; I think it is a result of the limitations of the flight model. This is a PC flight simulator and I think it's extremely difficult (if not impossible) to get real world stability in pitch/bank/yaw AND have 100% coverage of the real world behavior. I personally think the PC12 is an excellent plane and a joy to hand fly. From real world flying I know that the stability of especially pitch of most FS planes is way too unstable and the PC12 is a nice exception. Anyway, small tips: it seems on landing with flaps 30 instead of full I get less unrealistic pitch down behavior and make sure you plan the descent/speed early i.e. if you start the descent/approach high and fast, the effects become worse. Regards, Floris |
|
|
|
|
bradm10
New Member
Joined: August-15-2009 Location: United States Points: 6 |
Post Options
Thanks(0)
Quote Reply
Posted: August-16-2009 at 4:03pm |
|
I think you are too fast on final. At or before the final approach fix, bring the conditon lever back to about 40-60%; go to first flaps at 90 IAS, go to second flaps at 75 and slow airspeed down to 70kts or a bit less. Don't use full flaps unless you want to do your final at 60kts. The aircraft doesn't stall until you are about 50 kts. So if you are coming in at 110 kts, you are going to have to force the nose down. I've never flown a real PC-12 so I'm not sure how correct the modeling is. |
|
|
|
|
iflysioux
Intermediate Group 
Joined: May-30-2007 Points: 61 |
Post Options
Thanks(0)
Quote Reply
Posted: January-23-2010 at 9:52pm |
|
I've got a little bit of PC-12 time (like 6 hours) and yes it does fly and land, seemingly very nose low. Or at least it appears that way, you've got a 1200 hp engine up there and going down is not that airplane's forte. But from what it sounds like, depending on how you have it loaded it sounds about right.
|
|
|
|
|
RobertBuell
New Member
Joined: May-02-2010 Points: 12 |
Post Options
Thanks(0)
Quote Reply
Posted: May-02-2010 at 10:42pm |
|
On approach, I fly the angle of attack indicator regardless of flap setting. It'll tell you if you are too fast, too slow, "right on the money" or somewhere between. The airspeed indicator takes on a supporting instrument role.
|
|
|
|
|
luap
Certified Professional 
Joined: December-11-2003 Points: 8089 |
Post Options
Thanks(0)
Quote Reply
Posted: May-03-2010 at 10:30am |
|
I did a little experiment on this aircraft for someone a while back. At proper pitch and power settings, if you fly the manual specs for an approach, it's pretty spot on. Fly by the numbers and it behaves quite accurately. I was always of the opinion that it was a little overwraught on pitch attitide but then I did my homework and to my surprise, it was about what it should be. ... BUT YOU HAVE TO BE FLYING THE NUMBERS!... or else it seems like the nose is all screwey. |
|
 Paul Scott Bartelt The grass is always greener over the septic tank |
|
|
|
|
RobertBuell
New Member
Joined: May-02-2010 Points: 12 |
Post Options
Thanks(0)
Quote Reply
Posted: May-03-2010 at 1:50pm |
I think "fly by the numbers" is one of aviation's most fundamental rules. In the context of this thread, flying the approach with the angle of attack indicator centered gives you the right numbers. In fact, a centered AOA indicator is a PC-12 checklist item on both the Before Landing Checklist and Final Check Checklist. The item on both reads "Speed.............AOA CENTERED." |
|
|
|
|
MartinW
Senior Member 
Joined: December-28-2007 Location: United Kingdom Points: 185 |
Post Options
Thanks(0)
Quote Reply
Posted: July-31-2010 at 1:53pm |
|
The PC-12 does have a natural nose down attitude on approach. Two real world PC-12 pilots told to me that the pitch on a three degree glide slope, at the correct approach speed is two-three degrees down. 2 degrees down is also evident in the excellent Flight Video Productions video. Courtesy of a very nice close up of the PFD on the three degree approach, on speed with full flaps and gear down.
|
|
|
|
|
luap
Certified Professional
Joined: December-11-2003 Points: 8089 |
Post Options
Thanks(0)
Quote Reply
Posted: July-31-2010 at 3:15pm |
|
I Did a little comparison using an approach video and a screen shot. Doing my best to get everything setup in an identical fashion I took a frame from the video and an in game screen cap at the same perspective while on a dialed in approach and overlayed them, making one semi transparent. They lined up almost perfectly.... see this post.
Having once been a slighly annoyed at the PC-12 flight model for the same reasons, I currently consider it to be one of the more accurate now that I have been "edjamacated a lil' bit". I've flown 150's and 152's and 172's and piper 140's so those models I am perfectly suited to judge but not having flown a PC-12, it just never seemed right but critical evaluation shows that it is.
The PC-12 would be on my short list of aircraft to buy if I ever hit the lottery. Either that or a Caravan. GMC Suburban with wings.... although I am not sure I can haul my Johnson 18 up to the cottage behind a Caravan.
|
|
|
Paul Scott Bartelt The grass is always greener over the septic tank |
|
|
|
|
MartinW
Senior Member
Joined: December-28-2007 Location: United Kingdom Points: 185 |
Post Options
Thanks(0)
Quote Reply
Posted: August-01-2010 at 4:02am |
|
Yes but your overlay is an external view Paul, you can't see the PFD. The airports exact glide slope in degrees, the pilots exact airspeed at the time, and the pilot pitching up or down at that point are the variables you don't know.
You would need to see the PFD.
2-3 degrees is evident in the Flight Video productions video, and I can't think of anything more accurate, than a close up of the primary flight display of the real aircraft during approach. And 2-3 degrees down is suggested by the PC-12 pilots I mention. That's with all variables known and the same. On a three degree glide slope, full flaps, at the correct approach speed.
So the Flight1 rendition is pretty close, a fine piece of work.
Personally I use my own minor CFG tweak. Not that I'm advising others to do that.
Regarding the speed pointer on the PFD... It will only indicate the correct approach speed at max weight, 9921 lbs, it won't relate to anything other than 85 knots. [Unlike the real PC-12] At normal, lighter landing weights, it will pitch you down too low. my preference at the landing weights I favor, is to aim one dot lower.
|
|
|
|
|
DenisH
Intermediate Group
Joined: November-04-2009 Points: 91 |
Post Options
Thanks(0)
Quote Reply
Posted: September-29-2010 at 12:20pm |
|
I NOTE SOMEONE MENTIONED TO BRINK COND LEVER BACK> IS THERE A TUTORIAL SOMEWHERE THAT EXPLAINS HOW TO PROPERLY USE THE PROP RPM AND CONDITION LEVERS? (EXCUSE CAPS. MY KEYBOARD ON BLINK)
|
|
|
|
|
luap
Certified Professional
Joined: December-11-2003 Points: 8089 |
Post Options
Thanks(0)
Quote Reply
Posted: October-03-2010 at 3:44am |
|
There is no prop lever in the Pilatus, although your joystick may have an effect on the sim. Leave it full forward and ignore it.
If you are going to get max performance out of the aircraft, you will have to use the manual override (mouse grab in 2D view... don't ask me why).
Condition levers as indicated on the console - flight, ground and cutoff - which are all self explanatory terms. Place in the correct position for the situation.
|
|
|
Paul Scott Bartelt The grass is always greener over the septic tank |
|
|
|
|
DenisH
Intermediate Group
Joined: November-04-2009 Points: 91 |
Post Options
Thanks(0)
Quote Reply
Posted: October-03-2010 at 9:51am |
|
Thanks. That explains it.
|
|
|
|
|
bilby21
New Member
Joined: April-08-2015 Location: Australia Points: 8 |
Post Options
Thanks(0)
Quote Reply
Posted: April-08-2015 at 10:48am |
|
Keep full flap for STOL landings. Just use 2 stages of flap. The others are right. The real aircraft does cruise slightly nose low. My neighbour flies one. Unlike the default A321. The real bird cruises level, but the sim version shows about 2.5 degrees nose low. I don't know why, and it'll take someone a lot smarter than me to work out a fix.
|
|
|
I am what I am. If someone doesn't like it, that's their problem!
|
|
|
|
|
Post Reply
|
|
| Tweet |
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
Topic Options
luap wrote: