Partial panel
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From: UK
Partial panel
You have a working AI, magnetic compass and altimeter - nothing else including engine instruments.
You are IMC with a base 600 feet and a localiser approach available over land with no sea nearby.
In the first scenario you have a working radio and in the second you dont.
How would you approach the landing?
You are IMC with a base 600 feet and a localiser approach available over land with no sea nearby.
In the first scenario you have a working radio and in the second you dont.
How would you approach the landing?
Joined: Nov 2003
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From: Westward TV
fuji,
your scenario doesn't describe partial panel. that is when you loose your vacuum instruments, ie DI and AI. in that case your workload is much higher.
taking your scenarios though,
first, make sure you are above MSA. if not then full power and pitch the nose about 5 degrees up and climb. then, turn on your pitot heat as it sounds like this has iced up .
if you have a working radio then request assistance and vectors for the nearest SRA or PAR unit. this should be your first request. let someone else worry about your tracking and leave you to the difficult task of flying the thing in a straight line
just follow their instructions. they will give you left 10, right 20 type heading corections. so, remembering compass turns, it's either 3 seconds rate one for 10 degrees, 6 seconds for 20, so on. for rates of descend, try counting to 6 and seeing how much height you've lost. times this by 10 and you have a RoD.
now, if you dont have a working radio, then climb above MSA (if not there already) and make you the beacon overhead. set 7600. if you have file a plan and have given an EAT for the overhead, then thats when you start your approach. before you get to the beacon, check your compass heading and work out how long you need to turn to get on the outbound heading. at the beacon, turn onto your outbound heading. hold wings level and ball centred and check against the compass. wait. after about 2 miles outbound, you will begin to see whether you are left, right or on the outbound radial. the tricky part is to stay on the outbound radial or localiser. don't chase the needles and if you start to drift left or right then turn 10 degrees or three seconds) the other way, level the wings, check the ball and wait. you will then see either the radial/localiser move back towards the centre in which case, once the radial/localiser is centred, then a small turn back should help keep on the outbound radial or centreline.
the base turn will normally require a turn of about 210 degrees. so thats about 70 seconds at rate one. start the base turn and stopwatch. roll out on your expected heading and wait to see the effect on the localiser. again, if you're left, then turn right 10 degrees, wait and see the effect. once happy with your heading/tracking and reasonably well established on the localiser, then drop the flaps, set a lowish power and pitch the nose down about 2-3 degrees. check your not below heights on the profile and try and descend the aircraft as quickly and safely as possible. calculate and check your RoD. at 90 kts you want about 450 fpm for a three degree approach, however, the quicker you get down to MDA the better as once you are visual, the drama ends. of, and i would use the published MDA, not any of the IMC rating add 200 ft to your MDA nonsense.
if you don't have a radio and any radio navigation gizmos, then it is indeed a bad day for you. personally, i would climb to MSA, head due east for at least 90 minutes (fuel allowing for this of course). this should put me over the sea, then descend at a low RoD. the problem with this is that I would have no idea of the QNH over the sea so I would probably wind off 10 millibars from the altimeter as a fudge factor. hopefully you will get visual with the sea before you hit it. then turn back to blighty, and land at the first field you find.
i'm not saying it will be easy but it shouldn't be impossible. just don't panic and if you're not at all sure then climb the buggah back to MSA.
your scenario doesn't describe partial panel. that is when you loose your vacuum instruments, ie DI and AI. in that case your workload is much higher.
taking your scenarios though,
first, make sure you are above MSA. if not then full power and pitch the nose about 5 degrees up and climb. then, turn on your pitot heat as it sounds like this has iced up .
if you have a working radio then request assistance and vectors for the nearest SRA or PAR unit. this should be your first request. let someone else worry about your tracking and leave you to the difficult task of flying the thing in a straight line
just follow their instructions. they will give you left 10, right 20 type heading corections. so, remembering compass turns, it's either 3 seconds rate one for 10 degrees, 6 seconds for 20, so on. for rates of descend, try counting to 6 and seeing how much height you've lost. times this by 10 and you have a RoD.
now, if you dont have a working radio, then climb above MSA (if not there already) and make you the beacon overhead. set 7600. if you have file a plan and have given an EAT for the overhead, then thats when you start your approach. before you get to the beacon, check your compass heading and work out how long you need to turn to get on the outbound heading. at the beacon, turn onto your outbound heading. hold wings level and ball centred and check against the compass. wait. after about 2 miles outbound, you will begin to see whether you are left, right or on the outbound radial. the tricky part is to stay on the outbound radial or localiser. don't chase the needles and if you start to drift left or right then turn 10 degrees or three seconds) the other way, level the wings, check the ball and wait. you will then see either the radial/localiser move back towards the centre in which case, once the radial/localiser is centred, then a small turn back should help keep on the outbound radial or centreline.
the base turn will normally require a turn of about 210 degrees. so thats about 70 seconds at rate one. start the base turn and stopwatch. roll out on your expected heading and wait to see the effect on the localiser. again, if you're left, then turn right 10 degrees, wait and see the effect. once happy with your heading/tracking and reasonably well established on the localiser, then drop the flaps, set a lowish power and pitch the nose down about 2-3 degrees. check your not below heights on the profile and try and descend the aircraft as quickly and safely as possible. calculate and check your RoD. at 90 kts you want about 450 fpm for a three degree approach, however, the quicker you get down to MDA the better as once you are visual, the drama ends. of, and i would use the published MDA, not any of the IMC rating add 200 ft to your MDA nonsense.
if you don't have a radio and any radio navigation gizmos, then it is indeed a bad day for you. personally, i would climb to MSA, head due east for at least 90 minutes (fuel allowing for this of course). this should put me over the sea, then descend at a low RoD. the problem with this is that I would have no idea of the QNH over the sea so I would probably wind off 10 millibars from the altimeter as a fudge factor. hopefully you will get visual with the sea before you hit it. then turn back to blighty, and land at the first field you find.
i'm not saying it will be easy but it shouldn't be impossible. just don't panic and if you're not at all sure then climb the buggah back to MSA.
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From: EuroGA.org
I would reach for my handheld GPS and handheld radio and sort myself out with a DIY GPS descent somewhere, or get help from a radar unit if you can find one.
That's the obvious answer.
In your scenario, Fuji, I can't see there are any options if non-radio, and if you have a radio then you would get a radar letdown somewhere.
If truly out of options, all one can do is set up a minimum descent rate and descend, very slowly, and hope for the best.
Not sure how the localiser approach is relevant if you don't have anything with which to receive it.
In the UK, you will never be far from the sea so a timed leg offshore would be worth trying.
That's the obvious answer.
In your scenario, Fuji, I can't see there are any options if non-radio, and if you have a radio then you would get a radar letdown somewhere.
If truly out of options, all one can do is set up a minimum descent rate and descend, very slowly, and hope for the best.
Not sure how the localiser approach is relevant if you don't have anything with which to receive it.
In the UK, you will never be far from the sea so a timed leg offshore would be worth trying.
Thread Starter
Joined: May 2001
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From: UK
GHb
Thanks for your interesting reply.
Sorry I should have said this is a glass panel failure type scenario.
You only have AI, mag compass and altitude - nothing else - except maybe the radio.
(Loc only mentioned to give an indication of what assistance ground based radar might be able to give - accept that they may have a localiser without radar)
Thanks for your interesting reply.
Sorry I should have said this is a glass panel failure type scenario.
You only have AI, mag compass and altitude - nothing else - except maybe the radio.
(Loc only mentioned to give an indication of what assistance ground based radar might be able to give - accept that they may have a localiser without radar)
Last edited by Fuji Abound; 12th December 2006 at 14:10. Reason: Crossed with IO540 - also very interesting
Joined: May 2001
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From: 75N 16E
I suspect the glass cockpit has gone kaput. Has the backup ASI also gone?
S&L flight should not be too much of a problem, you can guestimate speed based upon common power settings.....egine sound / pitch / altimeter / known lever positions etc......
1) Request a PAR or SRA. If not available vectors to the FAF of the Loc approach and descend to correct altitude. At this point and altitude start descending down to minimums with radar guidance if available, or if not heading inbound course (which is protected with regards to terrain down to minimums). Come down quickly in this situation.
2) Pull the chute
Or pull my handheld GPS from the bag. Navigate to a the FAF of the loc approach and descend to required altitude, head on course using the handheld GPS, at the FAF start a descent down to minimums, or and make a perfect landing in time for tea and crumpets.
Do we not have any sort of nav kit in scenario 2? If not then you have to dead reckon your way to the FAF, whcih would be pretty tricky.
S&L flight should not be too much of a problem, you can guestimate speed based upon common power settings.....egine sound / pitch / altimeter / known lever positions etc......
1) Request a PAR or SRA. If not available vectors to the FAF of the Loc approach and descend to correct altitude. At this point and altitude start descending down to minimums with radar guidance if available, or if not heading inbound course (which is protected with regards to terrain down to minimums). Come down quickly in this situation.
2) Pull the chute
Or pull my handheld GPS from the bag. Navigate to a the FAF of the loc approach and descend to required altitude, head on course using the handheld GPS, at the FAF start a descent down to minimums, or and make a perfect landing in time for tea and crumpets.Do we not have any sort of nav kit in scenario 2? If not then you have to dead reckon your way to the FAF, whcih would be pretty tricky.
Last edited by englishal; 12th December 2006 at 14:20. Reason: Also crossed with the others
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From: .
You have a working AI, magnetic compass and altimeter - nothing else including engine instruments.
You are IMC with a base 600 feet and a localiser approach available over land with no sea nearby.
In the first scenario you have a working radio and in the second you dont.
How would you approach the landing?
You are IMC with a base 600 feet and a localiser approach available over land with no sea nearby.
In the first scenario you have a working radio and in the second you dont.
How would you approach the landing?
Well, I would start by praying!
Joined: Feb 2005
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From: England
Joined: Jun 2003
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From: EuroGA.org
gcolyer
I am not taking this bait anymore, so why don't you just give up?
FYI I was up at 5000ft today drilling holes in clouds, at -4C so with the prop de-ice on MAX, doing lazy eights, and was using the GPS to ensure I was in the right bit of airspace.
What would you do in the situation Fuji describes? Let's stick to posts that broaden knowledge, shall we? This isn't the Flyer forum.
I am not taking this bait anymore, so why don't you just give up?
FYI I was up at 5000ft today drilling holes in clouds, at -4C so with the prop de-ice on MAX, doing lazy eights, and was using the GPS to ensure I was in the right bit of airspace.
What would you do in the situation Fuji describes? Let's stick to posts that broaden knowledge, shall we? This isn't the Flyer forum.
Joined: Sep 2006
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From: Aylesbury,Bucks
Interesting scenario.
Please remember the G1000 (and other Glass pannels) are NOT one system. Just like flights instruments (clockwork) are NOT one system. But they have connected parts. So the whole system does not just fail.
e.g. Each Pannel on a G1000 has independent GPS, Radio, VOR and Fan's.
You need to look at failure as you would for normal instruments (e.g. vacum)
This is likely to be:
AHRS (only one!) - use backup AI and Mag compass
Pitot - (only one - normally) all airspeed use GPS + feel when landing
Audio Panel (Radio should auto set 121.5)
Single Panel (Reversionary mode) - Minor issue here is loss of moving map but still have 1 GPS , 1 VOR and 1 Radio (or two if some wierd fault)
Fan dead - shut down the appropriate panel - then as above.
If you cant get there before the battery dies or smoke (fan dead but you didnt know) then im with IO - get the backup GPS out of the bag and portable radio.
(I've often wondered how good the ones with VOR support are?)
Please remember the G1000 (and other Glass pannels) are NOT one system. Just like flights instruments (clockwork) are NOT one system. But they have connected parts. So the whole system does not just fail.
e.g. Each Pannel on a G1000 has independent GPS, Radio, VOR and Fan's.
You need to look at failure as you would for normal instruments (e.g. vacum)
This is likely to be:
AHRS (only one!) - use backup AI and Mag compass
Pitot - (only one - normally) all airspeed use GPS + feel when landing
Audio Panel (Radio should auto set 121.5)
Single Panel (Reversionary mode) - Minor issue here is loss of moving map but still have 1 GPS , 1 VOR and 1 Radio (or two if some wierd fault)
Fan dead - shut down the appropriate panel - then as above.
If you cant get there before the battery dies or smoke (fan dead but you didnt know) then im with IO - get the backup GPS out of the bag and portable radio.
(I've often wondered how good the ones with VOR support are?)
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From: England
Unless the electric master switch or the battery master relay fails. Check the appropriate circuit diagram.
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From: Aylesbury,Bucks
I'll check - but I have two master switches, one for each source.
Just checked - yes I have two power systems (Cessna 182) Alternator/Main Battery & Standby Battery which will operate with the master switch off (if it was armed at start) - this powers an "Essential Bus"
Just checked - yes I have two power systems (Cessna 182) Alternator/Main Battery & Standby Battery which will operate with the master switch off (if it was armed at start) - this powers an "Essential Bus"
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From: England
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From: EuroGA.org
denhamflyer
I know nothing about the G1000 internals but would be suprised if it has two separate backlight and backlight inverter systems.
I've had a number of laptops fail over the years and in most cases it was the LCD backlight that went.
I think one must assume that a failure will take out the whole panel.
I know nothing about the G1000 internals but would be suprised if it has two separate backlight and backlight inverter systems.
I've had a number of laptops fail over the years and in most cases it was the LCD backlight that went.
I think one must assume that a failure will take out the whole panel.
Joined: Sep 2003
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From: UK,Twighlight Zone
Well I have 2 electrical systems on my aircraft, one powered from the standard electrical system and one that powers the nav kit that is a Nmh battery, so if I lost the main system I could flick the switch and use the backup system.
As far as having a go at IO540, I would wager that he knows where he is ALL the time!! Don't assume that because he embraces modern technology he does not know the basics.
As far as having a go at IO540, I would wager that he knows where he is ALL the time!! Don't assume that because he embraces modern technology he does not know the basics.
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From: The Heart
"How would you approach the landing?"
Very carefully!
As Gushoneybun said, this isn't a standard failure scenario as the altimeter should also have failed.
Fly the aeroplane at the speed it is currently trimmed for and consider making a flapless landing to avoid configuration changes at low level.
Expect to stay on instrument to below the MDA for the approach (avoids stress when the ground doesn't appear at 600').
Get vectors for an SRA or PAR.
If none within range, find a VOR approach, probably be easier to identify the overhead position. Fly to the beacon and make a time based procedure.
When descending, maintain the trimmed speed until visual references have been established. You should know the approximate power setting for descent but just reducing by 3-500rpm should be enough to let you fly at the trimmed speed and an attitude 2 or 3 degrees below the horizon.
Needn't be a big deal.
Very carefully!
As Gushoneybun said, this isn't a standard failure scenario as the altimeter should also have failed.
Fly the aeroplane at the speed it is currently trimmed for and consider making a flapless landing to avoid configuration changes at low level.
Expect to stay on instrument to below the MDA for the approach (avoids stress when the ground doesn't appear at 600').
Get vectors for an SRA or PAR.
If none within range, find a VOR approach, probably be easier to identify the overhead position. Fly to the beacon and make a time based procedure.
When descending, maintain the trimmed speed until visual references have been established. You should know the approximate power setting for descent but just reducing by 3-500rpm should be enough to let you fly at the trimmed speed and an attitude 2 or 3 degrees below the horizon.
Needn't be a big deal.
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From: England
The PFD and MFD are identical, independent displays and if one fails, the critical information is presented on the remaining one. This should happen automatically, but there is a backup switch, just in case, and for testing it works.
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From: a galaxy far, far,away...
I'm astonished that so many people are mentioning vectors. You say "Pan-pan, pan-pan, pan-pan. I have multiple instrument failure, request a no-compass, no-gyro recovery for SRA"
That gets you identified, an appropriate radar service and "adopt the standard no-compass, no-gyro procedure; all turns rate one, starting and stopping on the executive word now"
You fly the plane, ATC do the work.
That gets you identified, an appropriate radar service and "adopt the standard no-compass, no-gyro procedure; all turns rate one, starting and stopping on the executive word now"
You fly the plane, ATC do the work.
Thread Starter
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From: UK
I had in mind a DA42 as my example.
The backup instruments are the AI, magnetic compass and altimeter. The AI is electric. There are no other backup instruments and no other radio navigation aids. (Other than whats in your flight bag). There is no manual engine instrumentation, although of course there is manual rudder and elevator trim, flaps and gear (although flaps and gear are electric, but dont worry if you run the backup battery dry because with diesels both engines are going to stop at that point anyway).
Primary systems can be displayed on either panel in the event one fails.
As IO540 says (perhaps in the very unlikely event) both backlights failed all the G1000 systems would be worthless (because there would be nothing to see if they were working). I am still researching the consequence of full AHRS failure (effectively the central computer through which the majority of the avionics operate).
However unlikely it is, a dual panel failure is what provoked my interest.
I suspect the reality would be you would also be without the "on board" radios becasue even if these continued to operate you would have no way of knowing what frequency was selected (although I suppose you could stay on the last selected, or if really clever might work out how many turns did what!!!
).
Perhaps it was in the mind of the designers that the backup instruments are only there to deal with selective failure of individual G1000 units (which after all is modular) - for example the loss of the glass AI.
Alternatively maybe it was in their minds you could survive on just the backup instruments which is what provoked my question. If that was so it might be odd that they did not also include a G/S perhaps - opinions please.
Of course I appreciate it is a cost versus risk scenario equation but for a "serious" IFR platform costing a very substantial sum a backup G/S is a very small percentage of the whole package.
(Personally I dont go any where without a GPS and radio in my bag - sorry if I fall into the pro GPS group, and as it happens I even put the liferaft in any twin I taking over water in spite of the ribing I always get).
The backup instruments are the AI, magnetic compass and altimeter. The AI is electric. There are no other backup instruments and no other radio navigation aids. (Other than whats in your flight bag). There is no manual engine instrumentation, although of course there is manual rudder and elevator trim, flaps and gear (although flaps and gear are electric, but dont worry if you run the backup battery dry because with diesels both engines are going to stop at that point anyway).
Primary systems can be displayed on either panel in the event one fails.
As IO540 says (perhaps in the very unlikely event) both backlights failed all the G1000 systems would be worthless (because there would be nothing to see if they were working). I am still researching the consequence of full AHRS failure (effectively the central computer through which the majority of the avionics operate).
However unlikely it is, a dual panel failure is what provoked my interest.
I suspect the reality would be you would also be without the "on board" radios becasue even if these continued to operate you would have no way of knowing what frequency was selected (although I suppose you could stay on the last selected, or if really clever might work out how many turns did what!!!
).Perhaps it was in the mind of the designers that the backup instruments are only there to deal with selective failure of individual G1000 units (which after all is modular) - for example the loss of the glass AI.
Alternatively maybe it was in their minds you could survive on just the backup instruments which is what provoked my question. If that was so it might be odd that they did not also include a G/S perhaps - opinions please.
Of course I appreciate it is a cost versus risk scenario equation but for a "serious" IFR platform costing a very substantial sum a backup G/S is a very small percentage of the whole package.
(Personally I dont go any where without a GPS and radio in my bag - sorry if I fall into the pro GPS group, and as it happens I even put the liferaft in any twin I taking over water in spite of the ribing I always get).
