Fists super low ILS

my 2 pennies

you were over exaggerating right? I know we all have "low approaches", where we descend to DH, see a light or two, continue.... see the RUNWAY or RUNWAY ENVIRONMENT or anything else listed under 91.175(c), and land. 91 or 135 who cares, we're already shooting the approach. If you honestly left......ok, nevermind--beating a dead horse.

Be careful what you do. Be careful what you tell people you do. Life is good. Your mom should spank you.
 
Here is my super-low ILS story for the day.

Yesterday, I went to RST (Rochester, MN) to pick up one passenger returning home from Mayo. There was low visibility around RST (and west) when I was scheduled to leave. Conditions were 1/4 mile visibility, 100' overcast, freezing fog, with a Remark that tower vis was 1/2 mile. Conditions east of there were much better, with clear skies just across the state line at LSE (LaCrosse, WI).

I had a little talk with the chief pilot to clarify that the first leg could be flown under Part 91 rules, even though it had to be counted towards 135 duty and flight time requirements (still not sure I understand that part correctly, but I'm working on it :) ). Because it was P-91 I could leave RST as my filed destination, LSE as alternate, and hope for conditions to improve prior to arrival as per the forecast. (If it had been a Part 135 flight I could not have departed while conditions at my destination were so low. I could have filed for LSE, though, and then diverted to RST if conditions were good enough at my arrival in the area.)

I checked conditions with Flight Watch during the trip. No improvement. When I got within range ATIS for RST was still advertising 1/4 mile, 100' overcast, FZFG. The next closest airport (which had been at 1400' ceiling, 7 miles) was down to 200 OVC (GPS approach there only). LSE was still clear, and ONA (Winona, MN) was calling 2100', 7 miles.

When MSP Center switched me over to RST approach, I checked in and asked about current conditions. Response was 1/4 - 100', touchdown RVR 1600 feet, midfield RVR 1800 feet. The ILS 31 (in use) has 2400 RVR limitation. I informed him of my probable intention to divert to ONA, but that I would like to continue and monitor conditions.

I then asked if anyone had tried the approach, and he told me that two planes had made it in (landed) within the last hour. He didn't mention any misses.

I continued with vectors for the approach, and descended until just above the cloud deck (4000 feet, I think). At that point I asked for an update, and was told RVR 1400. I then asked for the diversion and went to ONA.

Here was my train of thought: I was legal to attempt the approach, being under Part 91 rules. There was probably a decent chance of getting in based on the prior aircrafts' successful attempts. But, the problem was that I would be under Part 135 rules on the way out, and the conditions did not meet our minimums for departure. That would be a bugger, wouldn't it, to fly an approach to mins, land, then not be able to take off again until reported conditions improved? Therefore the decision was made to divert and have the pax drive 40 minutes to ONA.

Moral of the story? Eh, well, I don't have one. Just wanted to share some of my thoughts during the decision making process on that particular flight.

:)
 
How does that work, carrying passengers in that operation and being under part 91 rules? Did they not pay any money for the flight or were the employees of your company or something along those lines?
 
BrettInLJ said:
How does that work, carrying passengers in that operation and being under part 91 rules? Did they not pay any money for the flight or were the employees of your company or something along those lines?
I probably wasn't clear enough. The first leg to RST was empty. No pax. Picking up one at RST for trip home to Michigan. Sorry for the confusion.
 
SteveC said:
I probably wasn't clear enough. The first leg to RST was empty. No pax. Picking up one at RST for trip home to Michigan. Sorry for the confusion.

Gotcha. I sound like you made a good decision because I'm sure they wouldn't be to happy just sitting there at the airport not being able to takeoff.
 
I can't remember. Does "flight visibility" rule over twr and rvr under part 91? And then reversed for 135?
 
SteveC, sounds like you made an excellent decision! You were thinking about safety and the concern of the passenger. Now that's good PIC decision making.
 
graydog said:
SteveC, sounds like you made an excellent decision! You were thinking about safety and the concern of the passenger. Now that's good PIC decision making.

It sounds to me like SteveC was thinking how easy it would be for him to get STUCK at that airport.... its a known 91 in.. 135 out type trap. Air Ambulance folks deal with this when they fly empty to pick up a pax at some location with crappy wx.
 
Here's a quick little excerpt from one of my many instrument books. It makes determining visibility easy.
"The decision bar (1000ft from threshold) is a valuable aid in helping pilots guage in-flight visibility. If the aircraft is at the middle marker, and the runway threshold cannot be seen, you should look for the decision bar. If the middle marker is .6 miles (3600ft) from the runway threshold, and the decision bar is visible, then the visibility from the cockpit is 2600 ft. If the approach minimum calls for a half mile visibilty (2400ft), the minimum visibility requirement for landing is met. Similarly, if the middle marker is .5 miles (3000ft) from the threshold, and the decision bar is spotted but nothing is visible inside the decision bar, the estimated in-flight visibility is approximately 2000 ft. Based on this estimate, the approach minimum of a half mile visibility would not be met."

Not EVERY ILS has a middle marker of course but you get the point.
 
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