02 October, 2022 - Training: Anti-Ship/Case III/ Instrument Approach

For scheduled squadron missions.
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Hedgehog
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Re: 02 October, 2022 - Training: Anti-Ship/Case III/ Instrument Approach

Post by Hedgehog » Sat Oct 01, 2022 11:27 am

MrBean wrote:
Sat Oct 01, 2022 9:29 am
FWIW the Weather on mission day will not be as bad as it was in the video.
That's good, I suppose. I've been in the Caucuses range with Trim's real world weather enabled and absolute crap visibility, resulting in several go-arounds trying to land at KBL because I couldn't see the runway until I was over the threshold.

Real world question: who decides when visibility is too poor to allow landings at a field?

Also, commercial airliners, as I understand it, have advanced ILS systems that can pretty much land the plane by itself. Why would the Navy have aircraft that do not include something similar? (Not counting ACLS.)
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Lion
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Re: 02 October, 2022 - Training: Anti-Ship/Case III/ Instrument Approach

Post by Lion » Sat Oct 01, 2022 11:33 am

I think for shitty weather land-based recoveries, a ground controller talks you down on the approach path instead of using ICLS since our Hornet doesn't have ILS equipment installed. I forget what it's called.
It could technically be done in game with someone spectating in F2/F10 view.
Real world question: who decides when visibility is too poor to allow landings at a field?
There's standardized minimums set for every aircraft/type for how crappy the weather is allowed to be before you have to divert, i.e. cloud base 200 ft, visibility half a mile, stuff like that.

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Re: 02 October, 2022 - Training: Anti-Ship/Case III/ Instrument Approach

Post by Hedgehog » Sat Oct 01, 2022 11:42 am

Also, for some of us who don't have PPLs or real world ground school at some point, something important to understand (though my description will be somewhat simplified). In many cases, I think DCS Hornet pilots just select RDR ALT on deck before take-off and just leave it that way, which is typically fine, and maybe even safer for missions over 'indian territory.' However, to use the approach plates, you must be using BAROMETRIC ALTIMETER.

Which means you need to understand the difference between QFE and QNH.

For QFE, think "Field Elevation." It's the barometric pressure you dial in to your altimeter so that it will read '0' on the runway, even if you're in Denver and a mile above sea level. That's what ATC gives you when you request take-off. Seems like a good setting. I mean, when my wheels are on the runway, I'm at 0 feet, right?

Except the approach plate presents you with altitude requirements above sea level (ASL)!

So, yeah, you could probably fly an approach safely with radar altimeter to avoid hitting the ground, but it won't keep you from hitting obstructions and such. The approach plate altitudes keep everyone on standard approach patterns as well as keeping everyone safe from hitting things.

So to set your altimeter for ASL, you need QNH. Think "Nautical Height." (Above sea level. Nautical Height. Get it?) And we get the QNH from ATIS radio. And don't forget to set your ALT switch back to BARO.
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Re: 02 October, 2022 - Training: Anti-Ship/Case III/ Instrument Approach

Post by MrBean » Sun Oct 02, 2022 1:30 pm

Guessing alot of the QNH/QFE questions have already been answered by the video, but yes QNH is the altimeter setting that pretty much the whole world uses (except for certain former Soviet-bloc countries that still use QFE - and metric altitudes at that) Since DCS is coded/written by folks in one of those former Soviet-bloc countries, it still uses QFE in tower and ATIS communications. You will hear no mention of QFE anywhere in the world other than those few countries so is more confusing than it needs to be, sadly.

Lion is correct - each approach to each runway has a weather minimum specified for being able to use that approach. If that weather is below minimums, you won't break out of the clouds in time to see the runway. In the civilian world, FAA/ICAO rules prevent one from even trying to shoot an approach if the weather is known to be below minimums. In the military, however (at least in the Navy) one can shoot the approach and "hope for the best" in case you still break out in time to land. The Navy had a "general NATOPS" instruction (OPNAV 3710) that governed what weather you needed for primary and alternate requirements, and that is what we went by for flight planning purposes. I assume the AF has something similar.

The radar talk-down Lion mentioned is a "PAR" or Precision Approach - Radar. Just as he said, a ground based controller had a specialized radar display that shows the aircraft's lateral and vertical position with relation to the runway and they would give you azimuth and glidepath callouts periodically on your way in all the way to minimums which were pretty much similar to ILS minimums (usually 200' AGL and 1/2 mile from the runway, but sometimes 100' and 1/4 mile). That is what Hornet guys would typically have to utilize ashore if weather was below TACAN minimums, since most airfields do not have AACS. Also had to use it (shipboard was termed CCA or "Carrier Controlled Approach) on the boat if the AACS/ACLS equipment were inoperative.

As for why most military fighters don't have full ILS Category III capability (ILS to full autoland) guessing it is a combination of cost (expensive to install and maintain) and weight of the equipment. I don't know about autoland capabilities in large USAF transports like the C-5/C-17 that fly from point A to point B and take hours and hours to get there (like a civilian airliner) - but in fighters where one usually takes off - flies for an hour or two and lands at the same place, generally if the weather was going to be THAT bad, they just wouldn't go in the first place so the cost/weight of such CATIII autoland systems is likely not even close to worth it.

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Re: 02 October, 2022 - Training: Anti-Ship/Case III/ Instrument Approach

Post by Hedgehog » Sun Oct 02, 2022 1:57 pm

Is there a way to get QNH for fields in DCS that do not have an ATIS frequency?
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