Page 227 - Planning and Design of Airports

192 Airp o r t D e sign

3. The airport elevation
4. The mean daily maximum temperature for the hottest month
at the airport
5. The maximum different in elevation along the runway
centerline.
For the purposes of estimating runway length requirements, the
FAA groups aircraft by MGTOW. Based on the MGTOW of the critical
aircraft, the following procedures are defined:

Aircraft Less than 12,500 lb MGTOW
Critical aircraft less than or equal to 12,500 lb MGTOW are consid-
ered “small airplanes” for the purposes of estimating runway length
requirements. For these small aircraft, design runway length is based
on the aircraft’s reference approach speed, V .
ref
Aircraft with V < 30 kn are considered short takeoff and landing
ref
(STOL) aircraft. The design runway length for STOL aircraft is 300 ft
(92 m) at sea level. For airports at elevation above sea level, the design
runway length is 300 ft plus 0.03 ft for every foot above sea level.
For aircraft with 30 ≤ V < 50 kn, the design runway length at sea
ref
level is 800 ft (244 m). For airports at elevation above sea level, the
design runway length is 800 ft plus 0.08 ft for every foot above sea
level.
For aircraft with V ≥ 50 kn, the design runway length is based on
ref
the number of passenger seats in the aircraft. For those aircraft with
less than 10 passenger seats, Fig. 6-12 is referenced. This figure has
two sets of curves, one representing “95 percent of fleet,” to be used
at airports serving small communities, and one representing “100
percent of fleet,” to be applied at airports near larger metropolitan
areas.
Figure 6-12 is illustrated with an example case where the mean
daily maximum temperature at the hottest month at the airport is
59°F and elevation is sea level. A vertical line is drawn from the point
on the horizontal axis associated with 59°F to the sea level field eleva-
tion curve. A horizontal line is then drawn from the associated loca-
tion on the elevation curve to the right side of the figure. The value at
the end of the horizontal line on the right side of the figure is the rec-
ommended design runway length. In this case, applying the 95 per-
cent of fleet curve results in a design runway length of 2700 ft, while
the 100 percent of fleet curve resulting in a design runway length of
3200 ft.
For those aircraft with 10 or more passenger seats at airports at
elevation 3000 ft AMSL or less, Fig. 6-13 is referenced. At airports at
elevation greater than 3000 ft AMSL, Fig. 6-12 “100 percent of fleet” is
referenced.
Figure 6-13 is illustrated with an example case where the mean
daily maximum temperature at the hottest month at the airport is