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Richard Sennett

Altitude hold help

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Guys this will not adhere to a given alt on mcp it just blows right by it in either direction any help would be appreciated - thanks

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It's a bug

 

Unless you only select an ALT, and just use the scroll wheel on the left to change the vs target. (Don't actually use vs mode)

 

Since I fly online this is what I've been using. It's no FLC but at least it will ALTS . And it keeps me more involved, trying to climb at 250 kias.

 

Btw the reason FLC sucks is because their autopilit pitch modes are too laggy. What I mean is that when you change the pitch using the method above it takes quite some time to pitch up and down. Obviously we don't want instant changes as the virtual pax would pukin rally all over, but it's far too laggy.

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It's a bug

 

Unless you only select an ALT, and just use the scroll wheel on the left to change the vs target. (Don't actually use vs mode)

 

Thanks Ryan but it doesnt matter it will blow bye any alt I input spinning the knob will not fix that right ?

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I used the method you're mentioning Ryan for climbing, and descend all the way down to 6000. Below that when I was vectoring around for landing, it wasn't working at all. Damn near nose dives when I was turning to intercept the LOC.

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I used the method you're mentioning Ryan for climbing, and descend all the way down to 6000. Below that when I was vectoring around for landing, it wasn't working at all. Damn near nose dives when I was turning to intercept the LOC.

 

Yes not working I have tried for 2 days -  only way to navigate this bird is to get real familiar with your quadrant throttle and trim levers - expected a decent working hawker - I havent seen anything work including fms following - the heading select works great if you only want to go left and right

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I used the method you're mentioning Ryan for climbing, and descend all the way down to 6000. Below that when I was vectoring around for landing, it wasn't working at all. Damn near nose dives when I was turning to intercept the LOC.

 

Hmm mines working fine

 

Owe Carenado am apology on alt hold - just built a new pc and it has new 3.0 asmedia usb ports - I moved my controller to 2.0 usb and alt hold seems to be working now - hope FMS will be ok now - so if your having a problem you might want to check your usb functions

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expected a decent working hawker

 

Why ?

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Why ?

Now Now   :smile:

 

I still have to trim and throttle when you get to the designated alt or it will still go by it so no sure if thats correct

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Now Now :smile:

 

I still have to trim and throttle when you get to the designated alt or it will still go by it so no sure if thats correct

Hi Richard. I have a number of Carenado/Alabeo GA planes, the B1900 and then I got their E50 Phenom 100 and enjoyed it for a while but soon out grew it. I was tempted by the Citation 550 but opted out when I saw the reviews. With the H850XP I was hooked straight away and having had it for three days now I have to give Carenado full credit, I love flying this plane (my download was already ver 1.1). Not to say it is not without issues but I think Carenado have got the closest yet to matching the systems of the likes of PMDG and Majestic.

Straight away I have found that long distance FMS flight plans worked well with good system immersion (with the already mentioned exception to ILS approaches).

I think the issue you are seeing with Altitude select is that there are three modes depending on how you set up. ALT, ALTS and FLC. I have not been able to come to grips fully with FLS mode yet, but surfice to say that this plane does not have the normal Speed hold mode using Auto Throttle as in the B737. Instead FLC uses a very hairy method of Attitude trim to attempt to hold a speed. IMO this can lead to a catostropy in no time at all. For now I am avoiding this mode totally and opting to control speed manually once trim is estabilished. I have been able to estabilish this both in Manual flight by setting ALTS and trimming the throttle once stable on the set Altitude or in FMS flight plan mode waiting for the planned Altitude to be reached and attitude has stabalized, trimming the throttle.

 

I'm not sure as I'm not at home now but from memory setting ALTS is acheived in manual flight by pressing the ALT more than once and certainly after pressing NAV not VNAV.

 

When setting up a plan in the FMS, I inserted waypoints in the LEGS pages and then set the leg altitudes in the RLSK's with a proceeding "/" (eg. /34000, /5000 etc). Be aware that the default leg altitude is FL380.

 

As far as flight dynamics I find this plane is a real joy (I'm only a sim pilot so have no RW comparison to make). I found no problem in taking this plane for a few trips low and not real slow into some of the beautiful Fjords in ORBX's Norway (which I picked up at the same time as this plane thanks to thier May specials).

 

I'm still trying to sort out ILS approaches and see for myself if it is infact broken or whether its a case of learning the right technique for this plane.

 

Hope this helps a bit.

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Ok... here's a few tips regarding what the buttons do on a real Pro Line 21 autopilot:

 

ALT - When pressed captures and holds the aircraft's current altitude.  No more, no less.

VS - When pressed engages vertical speed mode to climb/descend.  This mode arms the ALTS mode for altitude capture.

FLC - When pressed engages flight level change mode to climb/descend.  This mode arms the ALTS mode for altitude capture.

 

Turning off either VS or FLC mode by pressing their button once again will revert to PTCH mode.  This mode also arms ALTS mode for altitude capture.  PTCH mode is also activated if a lateral mode is chosen and no vertical mode is active.

 

FLC has safety measures built into it to prevent the aircraft from stalling in a climb as well as overspeed protections.  VS mode has no safeties built into it at all.

 

VNAV is not a separate mode on the autopilot, but rather a way to trigger an enhanced mode of VS/FLC/PTCH.  VNAV doesn't just fly to altitudes in the flight plan but rather controls climb/descent based on altitude restrictions which can include 'at', 'at or above' and 'at or below' commands as well as the mysterious 'between'.  When VNAV is active, you would see the vertical mode names change to VVS, VFLC and VPTCH.  Also if the VNAV profile commanded an intermediate altitude you would see ALTV as a capture mode instead of ALTS.

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Thanks WarpD for the explanation.   To help me understand the VNAV operation...

 

Does this mean that the 850xp can follow altitudes from the FMC ...  as I understand it, normally it doesn't have an autothrottle built in.  Would that mean that the pilot has to monitor the FMC as to when it was about to climb or descend so he could manually introduce more power at the start of the climb or less at the start of the descent ?  ...also  how does the pilot check that the change in altitude between legs in the FMC is not too steep for the aircraft

 

I had been under the impression that 'manually operated throttle' aircraft were not capable of flying to FMC altitudes...  that these were there for pilot guidance only. 

 

Can I also ask  ....with the PTCH mode coming active when no other V mode is selected or NAV is selected  where does it start from ...  meaning,  does it continue at it's present attitude or does it level off if the pilot didn't enter the amount of PTCH he wanted to get to ALTS altitude ?

 

I hope you don't mind me asking...   just that Carenado don't seem to know and if the correct way the system works can be clarified here maybe they would read it or someone would post it to them so I and all of you can enjoy the Hawker as it's meant to be...

 

Thanks 

aero

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There's a limit to how much detail I'm willing to provide, after all this is my profession... building training systems with this knowledge.

 

However...

 

Yes, it will follow altitude restrictions.  No, it doesn't have an autothrottle.  The Pro Line 21 will alert the pilot 1 minute before it needs to either climb or descend so that the pilot can prepare.  As for 'too steep'.  It's all based on angles and the FMS knows if you're exceeding it's limits and tells you.  You might see a message like "UNABLE NEXT ALT" on the FMS.  Your impression regarding aircraft capabilities... I have no idea where you would get that from.  I've never heard such a statement.

 

PTCH mode captures current pitch and maintains it until needing to level off to capture an altitude.

 

Don't expect Carenado to make all of this happen.  They haven't the experience needed to accomplish it.

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Ok, here's how I've managed to get FLC working with the SP1 Hawker 850XP. I haven't made any other changes to the XML, .cfg or .air files. This doesn't necessarily reflect real world operation:

 

1. Set up your autopilot with a 250 knots IAS bug and your target FL (in my case, FL370). Also set your VS bug (the circle on the PFD) to about 1800 fpm.

 

2. FD on, the other autopilot switches off. (may not be relevant).

 

3. Set your takeoff power. If you're using full power, the trim should be set just before the TRIM annunciator light comes on. This will give you a nice 10 degrees pitch.

 

4. After takeoff, pitch to 10 degrees, lowering down to about 5-8 degrees depending on weight. Clean up the airplane (flaps/gears up)

 

5. You should see on the PFD, ROLL in green and ALTS in white. Autopilot at this stage should be off.

 

 

After you are done with the initial climb, you can set for cruise climb:

 

6. NAV mode engaged. This will switch to NAV mode on the PFD.

 

7. Switch on the AP master. This should switch you to ALTS in green on the PFD. The airplane is now using VS to climb. I didn't try climbing all the way but ALT SEL should be engaged and it should level you off.

 

8. Now switch on FLC. This should switch you to FLC at your chosen speed (or a few knots above/below it). FLC should now be displayed on your PFD along with your chosen speed. This should also level you off at the chosen altitude. I recommend switching on FLC when you're at about 240-247 knots depending on how quickly you are moving up the speed tape. Don't do it too early as it might want to pitch nose down to build up speed to expedite the FLC target climb speed.

 

9. Passing Mach 0.7, you can press the mach toggle (the same IAS speed knob) and set for Mach 0.7 to climb up to your chosen flight level.

 

 

Give this a try and see if it works. Seems to work okay for me.

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Great stuff guys - after work  have to sort thru all of this - but lol seems all we need to do is baby sit the throttles and a little trim lever action - hoping to get this to work outside the box so to speak with auto throttles - others say it works with saitek multi-panel - so guess what's on its way - I could not get key commands to work - looking forward to what others have to say

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There's a limit to how much detail I'm willing to provide, after all this is my profession... building training systems with this knowledge.

 

However...

 

Yes, it will follow altitude restrictions.  No, it doesn't have an autothrottle.  The Pro Line 21 will alert the pilot 1 minute before it needs to either climb or descend so that the pilot can prepare.  As for 'too steep'.  It's all based on angles and the FMS knows if you're exceeding it's limits and tells you.  You might see a message like "UNABLE NEXT ALT" on the FMS.  Your impression regarding aircraft capabilities... I have no idea where you would get that from.  I've never heard such a statement.

 

PTCH mode captures current pitch and maintains it until needing to level off to capture an altitude.

 

Don't expect Carenado to make all of this happen.  They haven't the experience needed to accomplish it.

 

 

Thanks very much  WarpD... it's really good of you to share this and that does clear up a few of my 'question marks'.  

 

aero

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