August 1996 Volume 39 / Number 8
IFR into VMC
Not many IFR flights get into trouble in visual conditions — it's usually the other way around. But transitioning from instruments to visual conditions during an approach presents a high workload, and the potential exists for a midair collision when VFR and IFR traffic start to mix. What follows is an analysis of a mishap that didn't happen — only because of a little luck. All of the elements of an accident chain were present.
A weak warm front covered the East Coast with marginal VFR and scattered light rain. Ceilings were variable, with a 1,000- to 1,200-foot overcast and visibilities ranging from four to seven miles. The tops of the clouds were at 4,000 feet. The destination for an IFR Beech Bonanza was a nontowered airport close to a large terminal area. Approach control advised the pilot to expect a transition route from a nearby VOR to an intersection on the localizer. Upon arriving at the intersection, the aircraft was cleared for the ILS Runway 23 approach and radar service was terminated. The pilot was told to cancel IFR on the remote clearance delivery frequency at the airport if unable to maintain contact with approach control because of low altitude.
Winds, according the automatic weather observation system (AWOS), were out of the northeast at five knots. The Bonanza pilot had listened to both the AWOS and unicom prior to reaching the final approach fix. Hearing no traffic, he decided to land straight in on Runway 23 and accept the slight tailwind component since the runway was 5,000 feet long.
Approach control was already vectoring other aircraft to follow on the approach as the Bonanza crossed the outer marker, still in the clouds. The pilot switched to the unicom and announced the position as "Outer marker inbound to Runway 23 for a straight-in approach." There was no response on the frequency.
The Bonanza pilot completed the before-landing check, turned on the landing lights, and began looking for the ground. At roughly 1,000 feet agl the runway became visible, so the pilot switched to the clearance delivery frequency to cancel IFR and allow the next IFR approach to begin.
Landing flaps were lowered, some final trim adjustments were made; and now the flight was slightly below glideslope, on speed, and on the localizer. That great "landing assured" feeling turned to surprise as a dark spot a few hundred yards ahead materialized rapidly into a Cessna 172 climbing out on Runway 5, head to head with the Bonanza. The pilot of the Cessna, in maximum climb attitude, never saw the Bonanza and passed about 100 feet overhead. There was no time to react or to begin any evasive maneuver. The VFR Cessna turned downwind to remain in the traffic pattern and dutifully announced his position on the unicom. It is unknown whether he made an announcement on takeoff while the Bonanza was canceling the IFR flight plan.
The accident report probably would have read, "Failure to see and avoid by both pilots," and there would have been a lot of finger pointing as to who was more at fault. Technically, the Bonanza pilot was operating under VFR at the time of the roof-to-belly pass, but the reality makes this perhaps a little more complicated.
The regulations give us much latitude at nontowered airports, which is good, but the responsibility is equally pervasive. This is one of those situations where pros and cons reside on both sides of the ledger. In Class G airspace, as exists up to 700 feet agl at this airport, all that is required is one mile visibility and clear of clouds to operate VFR — legal but not smart, particularly when there are IFR inbounds. The weather was considerably better than that in this scenario, and the Cessna pilot was properly taking off into the wind but against the IFR traffic flow. Two more IFR aircraft approached within the next 15 minutes. One circled to Runway 5 and one landed straight in on Runway 23. Apparently the VFR Cessna managed to avoid any more close encounters.
In the best Monday morning quarterback tradition, here are some questions to consider. Did the Cessna pilot anticipate IFR arrivals by listening on the approach frequency as well as broadcast his departure on the unicom? No — the Cessna pilot was oblivious to the other aircraft; and although we don't know if he heard the Bonanza announce the marker, he surely didn't take any preventive action.
Why didn't the Cessna use a landing light? This is a good idea on a sunny day, and even better on a dark cloudy one, to increase visibility significantly. Landing lights should be used whenever in the pattern. Some people will fuss about the cost of replacing bulbs; but given the chance of avoiding metal-to-metal contact, they sound like a dandy investment.
Why didn't the Bonanza just stay on unicom and cancel when on the ground? The Bonanza pilot was trying to be considerate and vacate the airspace quickly, but it would have been better to wait until on the ground and off the runway to cancel. Distractions in the landing phase are a leading cause of trouble; so, while it's not good to tie up the airspace for succeeding aircraft, a minute or two is not significant.
How about monitoring two frequencies, the unicom or common traffic advisory frequency and the inbound IFR frequency? Good idea for both VFR and IFR aircraft, assuming the aircraft is equipped with two radios (and most IFR aircraft are). It does get a little garbled at times, listening to two frequencies; but with practice it can be done successfully.
Should the Bonanza have circled to land? The judgment call on this one could go either way. It depends on the circumstances. How strong should the wind be before circling becomes inadvisable? If the wind is more than 10 knots, then that is generally a mandate to circle; it also depends on the length of the runway. The type of aircraft plays a part, as does the pilot's proficiency. Some aircraft have large flaps and land readily, while others have small flaps or are "floaters." Any aircraft can easily be turned into a floater if the pilot is liberal with airspeed, so staying on speed is important.
How low should the weather be before attempting to circle? In the daytime, the ceiling should be well above circling minimums — as in this case.
Suppose that the traffic inbound on the instrument approach is a twin or a jet, which is less maneuverable than a Bonanza and thus more demanding to horse out of a stable final approach configuration and into the circling maneuver.
There are other places where flying IFR into visual conditions poses a threat — climbing, descending, or breaking out of the side of a cloud deck. In this case we really need to depend on the VFR pilot to more than play by the rules. The regulation says that in Class E airspace below 10,000 feet, the closest you can come to a cloud is 2,000 feet horizontally. I've never been any good at estimating distances from clouds, and the time it takes for even a slow aircraft to emerge from a big puffy and get real personal is less than 10 seconds. I prefer a more leisurely introduction, thank you. Where both VFR and IFR exist in close proximity, we need to be thinking what those on the other side of the cloud are likely to do and fly defensively.
See also the index of "Safety Pilot" articles, organized by subject. Bruce Landsberg is executive director of the AOPA Air Safety Foundation.