Aeronautical Information Manual (AIM), page 396

Index   395 -- Page 396 -- 397

It is important to note that from 100 feet above the
TDZE and below, the flight visibility does not have
to be equal to or greater than the visibility prescribed
for the IAP in order to continue descending. It only
has to be sufficient for the visual references required
by 14 CFR part 91.175 (l)(4) to be distinctly visible

and identifiable to the pilot without reliance on the


2. Comparison of Visual Reference Require-
ments for EFVS and Natural Vision. Again, the
visual reference requirements for EFVS in 14 CFR
part 91.175 (l)(4) are more stringent than those re-
quired for natural vision in 14 CFR part 91.175 (c)(3).
The main differences for EFVS operations are that
the ALS and red terminating bars or red side row bars,
the REIL, and the VASI cannot be used as visual ref-
erences. Only very specific visual references from the
threshold or the TDZ can be used (that is, the lights
or markings of the threshold or the lights or markings
of the TDZ).

3. When to Go Around. A missed approach
must be initiated when the pilot determines that:

(a) The flight visibility is no longer sufficient

to distinctly see and identify the required visual refer-

ences listed in 14 CFR part 91.175 (l)(4) using natural


(b) The aircraft is not continuously in a posi-
tion from which a descent to a landing can be made
on the intended runway, at a normal rate of descent,
using normal maneuvers; or

(c) For operations under 14 CFR parts 121
and 135, the descent rate of the aircraft would not al-
low touchdown to occur within the TDZ of the
runway of intended landing.

While touchdown within the TDZ is not specifically
addressed in the regulations for operators other than
14 CFR parts 121 and 135 operators, continued oper-
ations below DA or MDA where touchdown in the
TDZ is not assured, where a high sink rate occurs, or
where the decision to conduct a missed approach pro-
cedure is not executed in a timely manner, all create
a significant risk to the operation.

4. Missed Approach Considerations. As
noted earlier, a missed approach initiated after the DA
or MAP involves additional risk. At 100 feet or less
above the runway, it is likely that an aircraft is signi-
ficantly below the TERPS missed approach obstacle

clearance surface. Prior planning is recommended
and should include contingencies between the pub-
lished MAP and touchdown with reference to
obstacle clearance, aircraft performance, and altern-
ate escape plans.

d. Light Emitting Diode (LED) Airport Light-

ing Impact on EFVS Operations. The FAA has

recently begun to replace incandescent lamps with
LEDs at some airports in threshold lights, taxiway
edge lights, taxiway centerline lights, low intensity
runway edge lights, windcone lights, beacons, and
some obstruction lighting. Pilots should be aware that
LED lights cannot be sensed by current EFVS sys-

5-4-23. Visual Approach

a. A visual approach is conducted on an IFR flight
plan and authorizes a pilot to proceed visually and
clear of clouds to the airport. The pilot must have
either the airport or the preceding identified aircraft
in sight. This approach must be authorized and
controlled by the appropriate air traffic control
facility. Reported weather at the airport must have a

ceiling at or above 1,000 feet and visibility 3 miles or

greater. ATC may authorize this type approach when

it will be operationally beneficial. Visual approaches

are an IFR procedure conducted under IFR in visual
meteorological conditions. Cloud clearance
requirements of 14 CFR Section 91.155 are not
applicable, unless required by operation

b. Operating to an Airport Without Weather
Reporting Service. ATC will advise the pilot when
weather is not available at the destination airport.
ATC may initiate a visual approach provided there is
a reasonable assurance that weather at the airport is a
ceiling at or above 1,000 feet and visibility 3 miles or
greater (e.g., area weather reports, PIREPs, etc.).

c. Operating to an Airport With an Operating
Control Tower. Aircraft may be authorized to
conduct a visual approach to one runway while other
aircraft are conducting IFR or VFR approaches to
another parallel, intersecting, or converging runway.
When operating to airports with parallel runways
separated by less than 2,500 feet, the succeeding
aircraft must report sighting the preceding aircraft
unless standard separation is being provided by ATC.
When operating to parallel runways separated by at
least 2,500 feet but less than 4,300 feet, controllers

5-4-60 Arrival Procedures

Page 396 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   395 -- Page 396 -- 397