Wednesday morning I devoted substantial attention to a strategy for avoiding icing issues during my flight to the DC area and planning to arrive at a time when I'd have good chance of completing the approach at KVKX.
I confess I didn't pay a lot of attention to the weather there in Bridgeport. When I looked out of my window I saw pretty good visibility and an overcast that had been running about 900 to 1,100 feet MSL for hours. So I was a little surprised that it was actively drizzling when I headed over to the airport and the ceiling and visibility had certainly deteriorated.
By the time I had pre-flighted N631S, picked up my IFR clearance and started the engine, this was the current METAR:
KBDR 251835Z 08004KT 1 1/2SM BR OVC003 09/09 A3000 RMK AO2 P0001
A mile and a half visibility and a 300 foot overcast qualifies as Low IFR in anyone's book. My late instructor, Bob Parks, had gotten me to practice "zero/zero" takeoffs "under the hood". But he also told me, "Don't take off from an airport that you can't get back into."
The wind was favoring Runway 6, which is the ILS runway at KBDR. I looked at the approach plate for the ILS RWY 6. It specified a Decision Altitude of 307 feet and minimum flight visibility of 1 mile. I decided to accept the 7 foot difference between the approach DA and the reported ceiling. Off I went, feeling that I could get back in using the ILS if something surprising happened.
Edit, 11/28: A couple of friends have pointed out that since the DA on the plate is in feet MSL and the ceiling in the METAR is in feet AGL, the values in this case were exactly the same in terms of feet above the 7' TDZE (Touchdown Zone Elevation). It's not a big factor at a near-sea-level airport like KBDR, but with a more substantial field elevation the difference would be more important (and presumably, more obvious).
I was promptly into the clouds. After the New York Approach controller got me radar identified she cleared me to 5,000 feet. I broke out of the lowest layer at about 3,500 feet and was into the clear between layers.
The rest of the flight worked out as planned. On this day, no need to return to the airport emerged. If one had (like, maybe, if my vacuum pump failure had picked 25 November instead of 12 October) I was pretty comfortable that I could fly the ILS to minimums and get back on terra firma. Of course, that comfort derived in part from the fact that I know the airport well and have probably done that approach 20 times.
Looking back I ask myself:
- Would I have been comfortable departing from an unfamiliar airport?
- How about if the ceiling was at 200 instead of 300?
- What if I was in an unfamiliar airplane (like a rental)?
- Suppose N631S had just come out of significant maintenance?
- What if it had been a couple of months since I'd flown an approach in actual IMC?
On every departure in challenging weather, there are lots of things to consider. As with most decisions, the Devil is in the details. On this occasion they added up to a "Go" decision with which I was comfortable.