Every pilot is taught flight operations in Class A airspace must be conducted under Instrument Flight Rules (IFR.) No exceptions. Right? Wrong! There are circumstances under which Visual Flight Rules (VFR) operations in Class A airspace are not only appropriate but required.
I'll bet most of you who have read the title of this article are already saying to yourself, "Visual Flight Rules (VFR) flight in Class A airspace is not permitted and you must have an Instrument Flight Rules (IFR) clearance to operate at or above FL180. This author must be crazy to try to write an article about a procedure that is definitely not permitted!"
This reaction is typical of pilots to whom I have presented the question outlined in the title. The correct answer to the question, however, is yes! There is a set of conditions when not only is it legal but you have no choice in the matter and you must conduct your flight under Visual Flight Rules (VFR) while in Class A airspace.
The set of conditions I am referring to applies in a situation where you lose all two-way radio communications while operating on an IFR clearance in Airspace A.
The reason for writing this article is that I believe I have discovered a gap in pilot knowledge. This gap reveals that most pilots are not aware it is possible to fly under VFR while operating in Class A airspace. The crew's experience level — whether a 20,000-hour airline captain or co-pilot, a military crew or a freshly minted instrument-rated private pilot — does not matter, nor does it matter if the aircraft is a C-5A transport, a F-15 Eagle or a Cessna Citation.
I first became aware of this gap approximately 30 years ago. At that time, I was the head of a company in the business of providing ground instruction for pilots and writing a course outline for my instructors to teach. The ground instruction was directed toward those pilots who desired to obtain an Instrument Rating or Air Transport Pilot certificate. While researching the loss of communications, I discovered the provision for VFR flight in what is now defined as Class A airspace.
|Level at FL350 Just East of PIT|
Let us imagine you are the captain of a Boeing 747-100 headed to Los Angeles (LAX) and have just leveled off at your cruise altitude of FL350 after taking off from John F. Kennedy airport (JFK.) In this case, I will put a little more pressure on you and include the situation that there is a very knowledgeable additional crew member on board your flight: a Federal Aviation Administration (FAA) Air Carrier Inspector on a routine line check of you and your crew.
"TWA 841 is cleared to the Los Angeles Airport via the Kennedy Seven Departure, with a Canarsie climb, direct to RBV J230 AIR J80 MKC J24 SLN ALS J44 FMN J64 CIVET, maintain FL350, squawk 6221"
The takeoff and departure are routine and you level off at FL350, approximately 50 miles west of Harrisburg on J80. The weather is "severe clear" and from your altitude, Greater Pittsburgh International Airport (PIT) will, very shortly, be in view. Now comes the fun for you and your crew as you discover that you have lost all communication capability.
No member of your crew or passengers has brought along a handheld VHF transceiver or cellphone. You are truly without communication capability. The proper setting of the transponder to code 7600 is one of the first items to be handled. What is the next proper course of action? (Remember, one of the FAA's finest is seated right behind you in the jump seat.) When I ask this question, most pilots will initially say that they are going to continue on to LAX via the routing and assigned altitude in the clearance that was last received.
91.185 IFR operations: Two-way radio communications failure.
(a) General. Unless otherwise authorized by ATC, each pilot who has two-way radio communications failure when operating under IFR shall comply with the rules of this section.
(b) VFR conditions. If the failure occurs in VFR conditions, or if VFR conditions are encountered after the failure, each pilot shall continue the flight under VFR and land as soon as practicable. (emphasis added)
Usually, the pilot will gloss over or not even read paragraph (b) which is the controlling part of the FAR. Note that it contains the word "shall," which when used in a regulation, gives the reader no option other than to comply. When directed to reread paragraph (b) very carefully, usually a look of consternation appears on the pilot's face when confronted by the word "shall."
The Airmans Information Manual (AIM)
The discussion then takes on a note of interest or puzzlement for the pilot because he has apparently never considered it before. It also gives me the opening to ask if we are in fact in "VFR" weather conditions. Most pilots answer, "We are in Class A airspace and no VFR operations are permitted here." This gives me the chance to direct the student to the Airmans Information Manual (AIM), which offers an expanded discussion about two-way communications failure in VFR weather conditions while in Class A airspace. The part that applies is in chapter 6 and reads as follows:
6-4-1. Two-way Radio Communications Failure...
2. VFR conditions. If the failure occurs in VFR conditions, or if VFR conditions are encountered after the failure, each pilot shall continue the flight under VFR and land as soon as practicable.
NOTE : This procedure also applies when two-way radio failure occurs while operating in Class A airspace. The primary objective of this provision in 14 CFR Section 91.185 is to preclude extended IFR operation by these aircraft within the ATC system. Pilots should recognize that operation under these conditions may unnecessarily as well as adversely affect other users of the airspace, since Air Traffic Control (ATC) may be required to reroute or delay other users in order to protect the failure aircraft. However, it is not intended that the requirement to "land as soon as practicable" be construed to mean "as soon as possible." Pilots retain the prerogative of exercising their best judgment and are not required to land at an unauthorized airport, at an airport unsuitable for the type of aircraft flown, or to land only minutes short of their intended destination.
Obviously, the note in the citation above specifically states VFR flight is permitted in Class A airspace if there is a two-way radio communication failure.
Occasionally a pilot will ask, "What is the minimum in-flight visibility and cloud clearance while in Class A airspace?" This can be answered by suggesting a close look at FAR 91.155, which says:
Sec. 91.155 Basic VFR weather minimums:
More than 1,200 feet above the surface and at or above 10,000 feet Mean Sea Level (MSL), 5 statute miles visibility, 1 mile from clouds and 1,000 feet below clouds and 1,000 feet above clouds.
By now, many pilots are convinced that you can operate under VFR in Class A airspace. I take this opportunity to suggest that it's time to reconsider our original course of action in light of these discoveries. (As you may recall, Flight 841 was going to proceed on to LAX via the original routing and at FL350.) Most pilots will look outside the window, spot Greater Pittsburg Airport (PIT) and announce they are going to proceed under VFR and land at PIT. I agree this is the correct course of action.
VFR and Part FAR Part 121 operations.
|*Formerly Air Transport Association|
This agreement essentially permits VFR flights operating within the terminal area, for good reason (such as ATC delays, excessive rerouting, etc.) to cancel their IFR flight plan or accept a VFR restriction for flights provided certain criteria are met. These criteria include VFR cloud clearance and visibility requirements and that the aircraft is receiving radar vectors by ATC. At uncontrolled airports, the pilot must be in direct communication with either tower, approach control, or departure control, etc.
More Food For Thought
No Radio communications (NORDO) In The Terminal Area...
We are now in agreement that proceeding to and landing at PIT under VFR is the proper course of action. But we now need to review the rarely-used procedures for landing at a major airport without an operating two-way radio. These include a discussion of the method of determining the proper runway (observe the windsock and the runway in use by existing traffic) and a review of the light signals (Airmans Information Manual chapter expected to be seen in this situation (a steady green light means "cleared to land").
...And The Proper Altitude
The landing at PIT covers the situation where a suitable airport is nearby when we experience our loss of communication. But what if the communications loss occurs when the nearest suitable airport is, for example, 600 miles west of our position? Of course, our last assigned altitude, FL350, is an IFR altitude. Since we must proceed under VFR, an altitude change is in order.
Some pilots suggest a descent be made to permit flight beneath Class A airspace. Although this would indeed be a legal course of action, the greatly increased fuel consumption at this lower altitude would not permit us to complete the flight with safe fuel reserves. The procedures concerning loss of two-way communications takes this situation into account by permitting us to maintain a higher, more efficient cruising altitude. The correct altitude for our continuing flight would be found in FAR 91.159:
Except while holding in a holding pattern of 2 minutes or less, or while turning, each person operating an aircraft under VFR in level cruising flight more than 3,000 feet above the surface shall maintain the appropriate altitude or flight level prescribed below, unless otherwise authorized by ATC:
a) When operating below 18,000 feet MSL and—
(1) On a magnetic course of zero degrees through 179 degrees, any odd thousand foot MSL altitude +500 feet (such as 3,500, 5,500, or 7,500); or
(2) On a magnetic course of 180 degrees through 359 degrees, any even thousand foot MSL altitude +500 feet (such as 4,500, 6,500, or 8,500).
(b) When operating above 18,000 feet MSL to flight level 290 (inclusive) and—
(1) On a magnetic course of zero degrees through 179 degrees, any odd flight level +500 feet (such as 195, 215, or 235); or
(2) On a magnetic course of 180 degrees through 359 degrees, any even flight level +500 feet (such as 185, 205, or 225).
(c) When operating above flight level 290 and—
(1) On a magnetic course of zero degrees through 179 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 300 (such as flight level 300, 340, or 380); or
(2) On a magnetic course of 180 degrees through 359 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 320 (such as flight level 320, 360, or 400).
FAR 91.159 clearly indicates a choice of a cruising altitude of FL360 would be more appropriate for our direction of flight. Possible choices would also include FL 185, FL205, FL225, FL245, FL265, FL285, FL320, FL400, FL480, FL520, FL560 and, of course, FL600 and above. Most pilots will agree that climbing to FL360 is a proper course of action.
Without the benefit of the above knowledge, most pilots would continue their flights after loss of two-way radio communications all the way to their destination. This would mean they could be operating in the system for as long as five hours or more without communications capability. This would cause ATC untold hardships as well as possible altitude and routing restrictions to other flights operating in the vicinity.
In addition, if your destination airport has no radar coverage, ATC is not permitted to authorize flight by other IFR aircraft in its airspace for a period of time of 15 minutes prior to your ETA and for as long as one hour after your ETA. If you continued on to your destination when a landing could have been made safely under VFR at an airport short of your destination, I can guarantee a greeting committee of an unfriendly nature upon your arrival.
To sum up, if you are operating in the Class A airspace and experience loss of two-way communications, you must proceed under VFR and land as soon as it is practicable. Provisions have been incorporated into the FARs to permit this safer course of action. The AIM actually encourages operation under VFR.
Lastly, I must add that all situations are different and it is up to the pilot-in-command to determine whether to use the pilot's emergency authority. Would you actually fly VFR in Airspace A to follow these procedures or would you chose not to? Why?
You can find this article originally as published by Avweb in the year 2000 (five years prior to the implementation of Reduced Vertical Separation Minima (RVSM) at: