January 28, 1992
(no name given)
This is in response to your October 24, 1991, letter in which you asked several questions about certain Federal Aviation Regulations (FAR).
First, you asked whether a clearance is required to operate in a control zone, "...when an aircraft is 5000 feet over the airport, in VFR conditions, but the airport itself is covered in low stratus." We assume from your scenario that the airport is at sea level and that the pilot of the aircraft is merely planning to transit the control zone at 5000 feet above ground level (AGL). FAR Section 91.155 lists the basic VFR weather minimums for certain altitudes, within and outside controlled airspace (14 CFR Sec. 91.155). A control zone is a type of controlled airspace. Using your example, if the pilot maintains basic VFR weather minimums and is transiting the control zone, he may enter a control zone at 5000 feet AGL without obtaining an ATC clearance.
Second, you questioned how low a pilot must descend (i.e., minimum descent altitude or decision height or full stop landing) on the six instrument approaches he must log to meet the recent IFR experience requirements specified in FAR Section 61.57(e)(1)(i) (14 CFR Sec. 61.57 (e)(1)(i)). You also asked if an instrument approach "counts" if only part of the approach is conducted in actual IFR conditions. Section 61.57(e)(1)(i) states that:
No pilot may act as pilot in command under IFR, nor in weather conditions less than the minimums prescribed for VFR, unless he has, within the past 6 calendar months - (i) In the case of an aircraft other than a glider, logged at least 6 hours of instrument time under actual or simulated IFR conditions, at least 3 of which were in flight in the category of aircraft involved, including at least six instrument approaches, or passed an instrument competency check in the category of aircraft involved.
For currency purposes, an instrument approach under Section 61.57(e)(1)(i) may be flown in either actual or simulated IFR conditions. Further, unless the instrument approach procedure must be abandoned for safety reasons, we believe the pilot must follow the instrument approach procedure to minimum descent altitude or decision height.
Third, you questioned the meaning of the phrase, "...in the vicinity of an airport...", as specified in FAR Section 91.103(a), Preflight action (14 CFR Sec. 91.103(a)). Section 91.103(a) provides that, "Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight. This information must include - (a) For a flight under IFR or a flight not in the vicinity of an airport, weather reports and forecasts, fuel requirements, alternatives available if the planned flight cannot be completed, and any known traffic delays of which the pilot in command has been advised by ATC;" We have no specific, fixed definition of "vicinity", but instead, interpret its meaning on a case-by-case basis.
Your fourth question concerns FAR Section 91.185, IFR operations: Two-way radio communications failure (14 CFR Sec. 91.185). You asked at what point may a pilot begin his descent for an instrument approach if he experiences communications failure when operating under IFR. Your example assumes the clearance limit is not a fix from which an approach begins. Section 91.185(b) provides that, "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." If the failure occurs in IFR conditions, or if Section 91.185(b) cannot be complied with, FAR Section 91.185(c)(2) specifies that the pilot shall continue the flight at the highest of the following altitudes or flight levels for the route segment being flown: (i) The altitude or flight level assigned in the last ATC clearance received; (ii) The minimum altitude (converted, if appropriate, to minimum flight level as prescribed in section 91.121(c)) for IFR operations; or (iii) The altitude or flight level ATC has advised may be expected in a further clearance. FAR Section 91.185(c)(3)(ii) provides, in pertinent part, that if the clearance limit is not a fix from which an approach begins, "...proceed to a fix from which an approach begins and commence descent or descent and approach as close as possible to the estimated time of arrival as calculated from the filed or amended (with ATC) estimated time enroute." In sum, if the communications failure occurs in IFR conditions, or if Section 91.185(b) cannot be complied with, the pilot maintains the highest of the altitudes or flight levels specified in Section 91.185(c)(2) for the particular route segment being flown until reaching the fix from which his approach begins. After reaching this fix, he may commence his descent as close as possible to the estimated time of arrival as calculated from the filed or amended estimated time enroute.
Fifth, you asked who is responsible for obtaining clearance through a restricted area when an aircraft is operating on an IFR clearance, and the ATC clearance assigns, "VFR conditions on top". If the aircraft is operating via a route which lies within joint-use restricted airspace, and if the restricted area is not active and has been released to the controlling agency (FAA), the ATC facility will allow the aircraft to operate in the restricted airspace without issuing specific clearance for it to do so. Conversely, if the restricted area is active and has not been released to the controlling agency (FAA), the ATC facility will issue a clearance which will ensure the aircraft avoids the restricted airspace, unless it is on an approved altitude reservation mission or has obtained its own permission to operate in the airspace and so informs the controlling facility. If the aircraft is operating via a route which lies within nonjoint-use restricted airspace, the ATC facility will issue a clearance so the aircraft will avoid the restricted airspace, unless it is on an approved altitude reservation mission or has obtained its own permission to operate in the airspace and so informs the controlling facility. These procedures are set forth in the Airman's Information Manual, paragraph 3-43.
Finally, you asked when a pilot can leave a fix, from which an approach begins, to commence his approach, if he is operating under IFR on a tower enroute clearance and experiences two-way radio communications failure. The procedures specified in FAR Section 91.185 (14 CFR Sec. 91.185) apply when operating under IFR on a tower enroute clearance. Section 91.185(c)(3)(i) provides that, "When the clearance limit is a fix from which an approach begins, commence descent or descent and approach as close as possible to the expect-further-clearance time if one has been received, or if one has not been received, as close as possible to the estimated time of arrival as calculated from the filed or amended (with ATC) estimated time enroute."
Please do not hesitate to contact us if you require any further information in this regard.
Sincerely,
Donald P. Byrne
Assistant Chief Counsel
Ignore the 6 hour requirement, that has since been removed from the regulations.