There’s a moment on every instrument approach, just as you are coming down to minimums where you start wondering just how accurate the equipment is and if you set everything up correctly. You normally don’t have much time to dwell on the possibilities of something not being right before you either break out and the wonderful, beckoning runway lights come into sight or you hit the bottom of the approach, don’t see anything and are frantically bringing up the power, cleaning up the airplane and pitching the nose up in an effort to get as far away from the rapidly approach ground, just as fast as you can. But in the seconds before you make the decision to land or go around, where you can’t see anything but swirling gray of clouds and mist in front of you, even in the warmest cockpits, you’ll feel a slight chill at the possibilities.
Yesterday started at 4am for me, with my alarm waking me from what felt like not enough sleep. This was day two of three and my 4th day in a row of waking up before 5am. After turning off both the hotel alarm clock (set to go off in 5 minutes in case my cell phone alarm failed) and then the still beeping cell phone, I started my early morning ritual of sneaking a quick look out the hotel window to see what the day was going to be like. In this case it involved moving the blinds back and looking out of the 11th story window, over a dark, wet and misty Kanawha river in Charleston, WV. From the reflections on the road in front of the hotel it looked like it was still raining and the flags across the street were stretched out due to the wind. Having wished I hadn’t looked outside I spent the next 35 minutes getting ready for work and absolutely not looking forward to the day.
The day actually didn’t start too badly. We managed to get right out of Charleston because of the early hour and despite a low layer of clouds and some heavy rain were descending through the mist and rain in Charlotte 30 minutes later. They vectored us around for the approach and even with the weather I had the runway in sight by about 500 feet off the ground. A quick turn (although I had enough time to run in through the raindrops and grab a bagel) and the FO was heading us east towards Wilmington. The ride out was exceedingly choppy but fortunately it smoothed out as we started our descent. He managed a nice landing on runway 17 despite the wind and we delivered our 24 passengers safely.
I took over flying duties and we taxied out with 40 people in the back. Of course, with the weather being down in Charlotte, and the later hour we were stuck waiting for 45 minutes so I shut down both engines and we admired the view from the side of the ramp. Wilmington is quite the happening place. Our penalty time served we started up again and taxied out to the runway. With the gusty wind I used full power for the take off (we can “flex” our take offs meaning we use the minimum amount we actually need to get off the runway and climb out safely as this saves wear and tear on the engines, but with the winds I wanted all the power I could get) and that combined with the light load had us rocketing up to 10,000 feet and turning south west towards Charlotte.
Because of the weather I had the radar on and it was painting a scattered mess across our route. We were able to work with Jacksonville Center and get a route that kept us out of the worst of it and mostly in the clear. We eventually were handed off to Charlotte Approach who vectored us towards runway 18C. As we entered the downwind for the instrument approach the radar started picking out large red splotches of heavy precipitation in front of us. The good news was the winds at 5000 feet were blowing at about 60 miles an hour and moving most of the weather off our route. The problem was there was a fair amount of stuff upwind that was now coming our way. A tight turn from Charlotte kept us out of the worst of it and we joined up on the ILS.
An ILS (or Instrument Landing System) is basically a radio beam projected from the runway up into the sky. It consists of two parts. A lateral “localizer” which provides horizontal guidance which allows you to stay centered on the runway from miles out even if you can see it, and a vertical “glideslope” which gives a constant rate descent right down to the runway. The ILS is ridiculously accurate and under normal conditions allows you to get to just 200 feet off the ground while only being able to see 1800 feet ahead of you and still land. Once you get 200 feet above the ground (which is listed as a set altitude on the approach plate) you either have to be able to find the runway (or the approach lights) or execute a go around. From the 200 foot point, if you continue the decent, you are normally on the ground in about 20 seconds so the decision has to come pretty quickly.
Now, heading inbound in moderate chop and heavy rain, the only thing visible in front of us was a mass of clouds, barely visible through the water running up the windshield as we barreled through the weather at 180 miles an hour. With the aircraft fully configured with the gear down and the flaps out I was able to slow to 150 miles an hour but we were still descending towards a runway we couldn’t see at 700 feet per minute. At 1000 feet above the ground the FO called out “1000”. I had the autopilot flying still as it does a better job (under normal conditions) of tracking the ILS in and was splitting my attention between making sure it was staying on target, monitoring the airspeed and power settings as well as sneaking glances out the front to see if I could see anything.
3 feet below us, embedded in the underside of the nose of the aircraft two radar altimeters were pinging away at the ground below us. Once the beam send and return time was computed at 500 feet the plane dutifully called it off for us however there was nothing visible outside to back up this assertion. I took a quick look at the approach plate and double checked (for about the 10th time) the minimum altitude for the approach and then glanced at the primary flight display to make sure it was set there as well. I then looked back at the plate to mentally rebrief what I’d be doing if we hit minimums and didn’t see anything. By the time I looked back at the displays we were just 200 feet above minimums and 400 feet off the ground, still with nothing but blurry gray mist and rain.
At 100 feet above minimums the FO called off “100 above” and I started to feel the chill that I always get, no matter how many times I do this when I am just 300 feet and less than 20 seconds from the ground and still don’t see anything. A second later the FO called the approach lights in sight and I took a quick glance forward and saw a hazy set of red and green lights with a the rabbit (a line of lead in strobe lights) running between them. Despite all the amazing things I see while flying, the runway lights emerging through a low ceiling and reduced visibility is one of the most beautiful. A quick flick of my wrist turned on the wipers and the lights got a little clearer. As the airplane called out “minimums” the runway lights appeared through the murk. I called out “runway in sight… landing” and turned off the autopilot. A quick bank to the left to account for the wind had me lined up with the center line and I kept the nose over to keep us descending towards the wet surface below.
At 100 feet above the runway I started pulling out the power. At 50 feet the airplane started calling off our altitude in increments of 10 feet and by 30 feet the power was all the way out. There is a moment where, especially when the runway is wet, the airplane can’t decide if it wants to keep flying or not. Gravity always wins in the end and we settled onto the runway just passed the 1000 foot markers. The thrust reversers unlocked as the main gear compressed and with air now being directed forward from both engines the plane started slowing. Some gently brake application further slowed us to the point I was able to stow the reversers and taxi clear of the runway.
Hours later as we headed into Charlotte for the third time that day after fighting our way through the weather all the way up to Detroit, we broke into a clear patch about 30 miles from the airport. A rainbow formed next to us as the sun started dropping to the horizon to the west.