The snow has stopped, and the approach controller is advising that the destination’s precision-approach runway is temporarily closed for plowing. The cleanup should be completed before you arrive.
You are flying in the clear, between layers, and it is becoming evident that an instrument approach will be required. Thinking ahead, you tell yourself that if the plowing operation isn’t finished before you get there, perhaps you will be cleared for the approach with a sidestep to the parallel runway.
Would circling values apply?
According to a flight instructor who corresponds with AOPA about intriguing questions concerning operational procedures, he noticed considerable discussion in aviation forums on sidestep clearances, prompting him to seek a conclusive response from the powers that be.
“Many people on the forums seem to think that you have to use the circle-to-land minimums if there are no side-step minimums published or it is not allowed (i.e. ATC would not say ‘side-step to 36L’ but would have to say ‘circle to RWY 36L’),” he wrote.
The experienced airman also offered his own theory, to the effect that “you can descend to the straight-in MDA (non-precision minimums, i.e. LOC if shooting the ILS) for the approach being conducted and then if you have visual reference, you can side-step to the adjacent runway.”
“However,” he added, “I can't find anything that specifically states that as a fact.”
According to the response he received from the FAA’s Flight Technologies and Procedures Division, “A clearance for a side-step maneuver to a parallel runway will only be granted when authorized by the instrument approach procedure. The side-step minimums for the approach will be published as a separate line of minima on the instrument approach chart.” An example of a correct clearance would be: “Cleared ILS Runway 12R, side-step to Runway 12L.” Side-step minima are always flown to a minimum descent altitude, the response added.
The response cautioned that if you are cleared to sidestep to a parallel runway without published sidestep minima, “you should query the controller.” That’s because “the only correct alternative in the absence of side step minima, is to instruct the pilot to 'Circle to...' which may result in a side step maneuver if the pilot chooses.”