ILS Categories. Do I have the right idea?
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ILS Categories. Do I have the right idea?
So this is what I understand so far.
If the visibility is 550 meters atleast / 1800ft, you are allowed to do a CAT 1 approach, where the minimum DH is at least 200 feet AGL.
Less than 550 M but not less than 350 M (1200) you are in for a cat 11 approach where a DH of atleast 100 feet.
Then come category 111
a: RVR 200 meters / 700 ft, and DH of atleast 100 ft.
b: RVR atleast 50 meters (150 ft), and DH atleast 50 ft.
c: auto land
Not just the numbers, but do I have the idea right?
What exactly is different with the different ILS categories except for the decision height? Speeds, etc. all remain the same?
Do you find the DH if you're doing CAT11, or CAT111 on the approach plate itself?
Is it ever possible that your RVR corresponds to a certain category, but your DH is too low for that ILS category?
Thanks guys!
If the visibility is 550 meters atleast / 1800ft, you are allowed to do a CAT 1 approach, where the minimum DH is at least 200 feet AGL.
Less than 550 M but not less than 350 M (1200) you are in for a cat 11 approach where a DH of atleast 100 feet.
Then come category 111
a: RVR 200 meters / 700 ft, and DH of atleast 100 ft.
b: RVR atleast 50 meters (150 ft), and DH atleast 50 ft.
c: auto land
Not just the numbers, but do I have the idea right?
What exactly is different with the different ILS categories except for the decision height? Speeds, etc. all remain the same?
Do you find the DH if you're doing CAT11, or CAT111 on the approach plate itself?
Is it ever possible that your RVR corresponds to a certain category, but your DH is too low for that ILS category?
Thanks guys!
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mate if you haven't done the course you don't need to know.
Stick to the cat 1 stuff if you do it to mins its well scary (trust me I have done it enough)
Its really not a subject for private flyers.
Unless you are of course a walt flight sim tosser
Stick to the cat 1 stuff if you do it to mins its well scary (trust me I have done it enough)
Its really not a subject for private flyers.
Unless you are of course a walt flight sim tosser
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Its really not a subject for private flyers.
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because you need approval from your CAA.
You also need the aircraft maitained to a differnet standard.
The crew need to do certain training at intervals. An extra day in the sim is normal evey 6 months.
The crew also needs to stay current at it and also the aircraft needs to do so many per month as well.
Unless you are under an audited QA system you haven't a chance in hell of getting approval.
And as wanky as the G1000 is it doesn't have the fail passive systems for CAT II or never mind the fail safe for CAT III a or b.
You also need the aircraft maitained to a differnet standard.
The crew need to do certain training at intervals. An extra day in the sim is normal evey 6 months.
The crew also needs to stay current at it and also the aircraft needs to do so many per month as well.
Unless you are under an audited QA system you haven't a chance in hell of getting approval.
And as wanky as the G1000 is it doesn't have the fail passive systems for CAT II or never mind the fail safe for CAT III a or b.
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What exactly is different with the different ILS categories except for the decision height? Speeds, etc. all remain the same?
Speed depends on the aircraft, its configuration and the weather.
Is it ever possible that your RVR corresponds to a certain category, but your DH is too low for that ILS category?
Everything > CAT I is reserved for the professional world. Flying at CAT I minima in a SEP can be quite scary. Synthetic vision and radar altimeters are good things to have.
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With regard to the original question, I don't see any harm in answering ... So here goes.
- Yes you are correct on the numbers
- Cat II and Cat III require special authorisation of the crew and aircraft. So your personal minimuqms are defined in that approval rather than some generic approach plate.
- Cat III requires lots of sophisticated equipment and training (two crew are definitely required and I suspect two turbines to push all the gear as well)
- In the US it is actually possible to get cat II in a single crew single piston engine aircraft (I believe it needs radar altimeter appropriate autopilot, flight director and I suspect two separate ILS receivers and displays)
- I don't have the authorisation, but I believe the speeds used are similar and the piloting difference starts with the requirement to fly to US ATPL standards and then moves on to other difference once below 100 feet.
- Finally, I have been told there are no civil IIIc approaches due to the lack of effective ground guidance to get from the runway to the terminal with no visibility
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mm_flynn
Thanks very much for the response.
Another question. I been watching videos of ILS approaches and I can't seem to understand why on the Flight Mode Announcement of the PFD it says sometimes "cat 111 single" and sometimes "cat 111 dual".
What exactly do these means?
Thanks!
Thanks very much for the response.
Another question. I been watching videos of ILS approaches and I can't seem to understand why on the Flight Mode Announcement of the PFD it says sometimes "cat 111 single" and sometimes "cat 111 dual".
What exactly do these means?
Thanks!
FWIW I have a very vague and probably thoroughly incorrect recollection that somebody, possibly Alaskan, have approval for hand flown ILSs to CAT II minima using a HUD.
For the OP: Whilst the videos can make autoland and Low Vis Ops looks like an exercise in button pushing and then sitting back, relaxing and enjoying the flight there is the (obvious?) possibility of failures of ground and/or aircraft equipment that can be very subtle and if gone unnoticed can very rapidly ruin your entire day. Hence the reason the pros have to retrain and requalify for <CAT1 Ops on a regular ( usually annual) basis)
For the OP: Whilst the videos can make autoland and Low Vis Ops looks like an exercise in button pushing and then sitting back, relaxing and enjoying the flight there is the (obvious?) possibility of failures of ground and/or aircraft equipment that can be very subtle and if gone unnoticed can very rapidly ruin your entire day. Hence the reason the pros have to retrain and requalify for <CAT1 Ops on a regular ( usually annual) basis)
A large proportion of professional pilots, or private pilots, will never fly other than a Cat 1 as well - but it does no harm for them to understand what other people are up to even then.
Although perhaps it might have been a better question in Tech Log, it's being answered here, and reasonably so.
G
(Moderator, asking nicely that we don't turn this into a pi$$ing contest please.)
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Hand Flown CAT3
I to seem to remember at least one airline in the USA hand flying CAT3 aproaches using a HUD. I think it was Air Alaska with the B727.
Or may be it is my old brain playing tricks on me!
Or may be it is my old brain playing tricks on me!
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Its really not a subject for private flyers. Its really not a subject for private flyers.
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Come on MJ, having a bad day?
The OP had a valid question.
FWIW, I know of somebody who got Cat 2 approval for a twin turboprop (Commander) and that was single pilot, and single autopilot.
The advantage was minimal; IIRC DH drops from 200ft to 150ft which is frankly barely worth the extra effort, but it does mean that when the airport goes officially "CAT2 / low visibility procedures" in the ATIS (e.g. this trip) you can legally land there, whereas if you landed anyway (which with an autopilot driving the LOC+GS you obviously could, in CAT2 conditions) you would draw an awful lot of "attention". This private pilot, who had unlimited funding, chucked in his aviation career suddenly after climbing all the way to the top of the food chain because, in his words, he got fed up with running an airline.
BTW, Cat 2 is CAT II but not Cat 11 (CAT eleven). CAT 3 is Cat III but not Cat 111 (CAT one hundred and eleven)
The OP had a valid question.
FWIW, I know of somebody who got Cat 2 approval for a twin turboprop (Commander) and that was single pilot, and single autopilot.
The advantage was minimal; IIRC DH drops from 200ft to 150ft which is frankly barely worth the extra effort, but it does mean that when the airport goes officially "CAT2 / low visibility procedures" in the ATIS (e.g. this trip) you can legally land there, whereas if you landed anyway (which with an autopilot driving the LOC+GS you obviously could, in CAT2 conditions) you would draw an awful lot of "attention". This private pilot, who had unlimited funding, chucked in his aviation career suddenly after climbing all the way to the top of the food chain because, in his words, he got fed up with running an airline.
BTW, Cat 2 is CAT II but not Cat 11 (CAT eleven). CAT 3 is Cat III but not Cat 111 (CAT one hundred and eleven)
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I been watching videos of ILS approaches and I can't seem to understand why on the Flight Mode Announcement of the PFD it says sometimes "cat 111 single" and sometimes "cat 111 dual".
Normally only one autopilot will be engaged, but during an autoland in low vis, all autopilots will be engaged to provide redundancy and error checking (look up fail passive/fail operational for more info).
The single/dual displayed on the PFD is indicating that one/two autopilots are in operation respectively (I'm guessing it was a 737 you were watching?).