521 

Federal Aviation Administration, DOT 

§ 135.609 

specified in this section, the FAA must 
publish notice of change in the F

ED

-

ERAL

R

EGISTER

and the material must 

be available to the public. All approved 
material is available for inspection at 
the FAA’s Office of Rulemaking (ARM– 
1), 800 Independence Avenue SW., Wash-
ington, DC 20591 (telephone (202) 267– 
9677) and from the sources indicated 
below. It is also available for inspec-
tion at the National Archives and 
Records Administration (NARA). For 
information on the availability of this 
material at NARA, call (202) 741–6030 or 
go to 

http://www.archives.gov/fed-

eral

_

register/code

_

of

_

federal

_

regulations/ 

ibr

_

locations.html. 

(1) U.S. Department of Transpor-

tation, Subsequent Distribution Office, 
DOT Warehouse M30, Ardmore East 
Business Center, 3341 Q 75th Avenue, 
Landover, MD 20785; telephone (301) 
322–5377. Copies are also available on 
the FAA’s Web site. Use the following 
link and type the TSO number in the 
search box: 

http://rgl.faa.gov/Regu-

latory

_

and

_

Guidance

_

Library/rgTSO.nsf/

Frameset?OpenPage. 

(i) TSO C–194, Helicopter Terrain 

Awareness and Warning System 
(HTAWS), Dec. 17, 2008. 

(ii) [Reserved] 
(2) RTCA, Inc., 1150 18th Street NW., 

Suite 910, Washington, DC 20036, tele-
phone (202) 833–9339, and are also avail-

able on RTCA’s Web site at 

http:// 

www.rtca.org/onlinecart/index.cfm. 

(i) RTCA DO–309, Minimum Oper-

ational Performance Standards 
(MOPS) for Helicopter Terrain Aware-
ness and Warning System (HTAWS) 
Airborne Equipment, Mar. 13, 2008. 

(ii) [Reserved] 

§ 135.607 Flight Data Monitoring Sys-

tem. 

After April 23, 2018, no person may 

operate a helicopter in air ambulance 
operations unless it is equipped with an 
approved flight data monitoring sys-
tem capable of recording flight per-
formance data. This system must: 

(a) Receive electrical power from the 

bus that provides the maximum reli-
ability for operation without jeopard-
izing service to essential or emergency 
loads, and 

(b) Be operated from the application 

of electrical power before takeoff until 
the removal of electrical power after 
termination of flight. 

§ 135.609 VFR ceiling and visibility re-

quirements for Class G airspace. 

(a) Unless otherwise specified in the 

certificate holder’s operations speci-
fications, when conducting VFR heli-
copter air ambulance operations in 
Class G airspace, the weather mini-
mums in the following table apply: