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Cessna 550 / 551 Citation II

Postby Drdawidventer » Mon Feb 18, 2019 7:19 pm

Good day

I'm trying out the above mentioned aircraft and experiencing problems with the AP Approach.

The glideslope is initially followed, but a few miles out - the aircraft abruptly pulls up, losing control and crashing.

Same thing happens with both the 550 and the Citation II.

Have no problems with the other aircrafts' AP and Approach.

Any advice?

Regards
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Re: Cessna 550 / 551 Citation II

Postby wkitty42 » Mon Feb 18, 2019 7:25 pm

turn off the AP and fly it in by hand? ;)
"You get more air close to the ground," said Angalo. "I read that in a book. You get lots of air low down, and not much when you go up."
"Why not?" said Gurder.
"Dunno. It's frightened of heights, I guess."
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Re: Cessna 550 / 551 Citation II

Postby Drdawidventer » Mon Feb 18, 2019 7:32 pm

Yeah, could try that..... New to flight and flight simulation, didn't known about all the AP stuff - really interesting, and wanted to try it out on the Citation 550 / 551 after a few successful landings with the 172 and 180s. Suck at manual approach. Thanks for the reply though.
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Re: Cessna 550 / 551 Citation II

Postby WoodSTokk » Tue Feb 19, 2019 8:09 am

The AP disconnects at 500 AGL.
This means, you must hold an eye on the radar altimeter while AP is on and in approach mode.
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Re: Cessna 550 / 551 Citation II

Postby Drdawidventer » Tue Feb 19, 2019 6:33 pm

Nope, occurs at an altitude of 3000-4000. Trying to make a video of it to share on the forum, but the AP goes completely haywire now. Cant even get it to initiate the approach at the moment.... :(
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Re: Cessna 550 / 551 Citation II

Postby Drdawidventer » Tue Feb 19, 2019 6:47 pm

Seems like the best small / light aircraft remain the 172 and 180s. Others all have issues.
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Re: Cessna 550 / 551 Citation II  

Postby stuart » Wed Feb 20, 2019 11:44 am

Hi,

A couple of thoughts:

1) Is it possible that the aircraft is stalling because you've not got sufficient power? On some AP modes, the aircraft will following the glideslope by adjusting the pitch. If power is set too low, it will be descending at below the glideslope rate. In this case the AP will command more and more pitch up until it stalls. I've encountered this myself when tuning the autopilot for the FG1000 C182T.

2) Are you approaching the glideslope from above or below? Normally you approach it from below from level flight. If you are approaching it from above, it's likely that the AP will overshoot, descend below the glideslope and then have to make a huge correction.

I would suggest ensuring you are completely familiar with the 172/182 and how the autopilot and ILS system works before moving onto more complex aircraft. That way you'll ahve a much better understanding of what the AP is doing. Just like in real life :).

-Stuart
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Re: Cessna 550 / 551 Citation II

Postby N77CB » Thu May 28, 2020 9:13 pm

AP must be in the Approach Mode for the Nav GS to work properly. At 500 AGL the AP will disengage and if your speed and flap settings are within landing parameters, you should only need minor inputs to flare and touch down
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Re: Cessna 550 / 551 Citation II

Postby Ysop » Thu May 28, 2020 10:15 pm

Drdawidventer wrote in Tue Feb 19, 2019 6:47 pm:Seems like the best small / light aircraft remain the 172 and 180s. Others all have issues.


It really depends, what you are looking for. "all have issues" is definitely not true. There is the tendency, that the ones discussed in this forum are under constant development and have therefore a higher quality. Of course there are exceptions to this rule.

wkitty42 wrote in Mon Feb 18, 2019 7:25 pm:turn off the AP and fly it in by hand?


Oh, so true. One day hand flying skill will completely diminish. Just like new generations being completely clueless and useless, when they should find their way with a paper map in their hand.
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Re: Cessna 550 / 551 Citation II

Postby MouseMaster » Fri May 29, 2020 9:01 pm

I fly this a lot. Here's my guess as to what you're doing wrong.

You're likely coming in below the glideslope but with Approach mode activated. At ~10nm out the aircraft pitches up when it detects that you're below the GS. Key: approach in Nav mode, level-ish flight, watch the GS indicator at the bottom left. Apply approach mode when the needle closes on the centre.

Approach power needs to be in the 56% range at typical weight. If you start falling too low up the power, reduce if you're too high, you need to pre-empt this because of the delay spooling the engines up/down. After 500ft keep the same discipline for manual flight, aim for a threshold speed around 120kts with full flaps.

If you're doing a std approach with a flightplan the Altitude Selector will change based on approach waypoint elevations, beware. These are a useful way to check what height you'll need to be at to intercept the GS, and you can set one in route-planner without needing a full plan.
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Re: Cessna 550 / 551 Citation II

Postby N77CB » Mon Jul 13, 2020 2:41 pm

MouseMaster has some good advice
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Re: Cessna 550 / 551 Citation II

Postby scarymovie » Thu Oct 29, 2020 3:58 pm

Hi everyone,

This is my new favorite aircraft in FG. The only problem I have with it is every time I landed on the runway, it rolls a little and then swerves to the side uncontrollably. Rudder, brakes don't help at all. Not sure what I am doing wrong here.

Thank you.
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Re: Cessna 550 / 551 Citation II

Postby WoodSTokk » Thu Oct 29, 2020 4:03 pm

Maybe you have strong wind. There is a bug in the FDM (YaSim) that we can not fix on aircraft side.
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Re: Cessna 550 / 551 Citation II

Postby scarymovie » Thu Oct 29, 2020 4:07 pm

WoodSTokk wrote in Thu Oct 29, 2020 4:03 pm:Maybe you have strong wind. There is a bug in the FDM (YaSim) that we can not fix on aircraft side.


Thank you for your response, WoodSTokk. Ah, that explains why I could do it with DHC-6 but not Citation even though I tried to land it a million times. Guess I will have to give up on it until there is a fix.
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Re: Cessna 550 / 551 Citation II

Postby Ysop » Thu Oct 29, 2020 4:22 pm

No worries mate. A bit of a "fix" is already in progress for some time.
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