AIM 

4/20/23 

(6) 

All doors, windows, and access points allowing entry to the interior of the helicopter that are 

adjacent to or in the immediate vicinity of the fuel inlet ports kept closed during HRR operations. 

(7) 

Pilots ensure that appropriate electrical/electronic equipment is placed in standby

−

off position, to 

preclude the possibility of electrical discharge or other fire hazard, such as [i.e., weather radar is on standby and 

no radio transmissions are made (keying of the microphone/transmitter)]. Remember, in addition to 

communications radios, radio transmissions are also emitted by aircraft radar, transponders, ADS

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B equipment, 

radar altimeters, DME equipment, and ELTs. 

(8) 

Smoking be prohibited in and around the helicopter during all HRR operations. 

The HRR procedures are critical and present associated hazards requiring attention to detail regarding quality 

control, weather conditions, static electricity, bonding, and spill/fires potential. 
Any activity associated with rotors turning (i.e.; refueling embarking/disembarking, loading/unloading 

baggage/freight; etc.) personnel should only approach the aircraft when authorized to do so. Approach should 

be made via safe approach path/walkway or “arc”

−

 

remain clear of all rotors. 

NOTE

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1. 

Marine vessels, barges etc.: Vessel motion presents additional potential hazards to helicopter operations (blade flex, 

aircraft movement). 

2. 

See 

National Fire Protection Association (NFPA) Document 407, “Standard for Aircraft Fuel Servicing” 

for 

specifics regarding non

−

HRR (routine refueling operations). 

10

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2

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2.  Helicopter Night VFR Operations 

a.  Effect of Lighting on Seeing Conditions in Night VFR Helicopter Operations 

NOTE

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This guidance was developed to support safe night VFR helicopter emergency medical services (HEMS) operations. The 

principles of lighting and seeing conditions are useful in any night VFR operation. 

While ceiling and visibility significantly affect safety in night VFR operations, lighting conditions also have a 

profound effect on safety. Even in conditions in which visibility and ceiling are determined to be visual 

meteorological conditions, the ability to discern unlighted or low contrast objects and terrain at night may be 

compromised. The ability to discern these objects and terrain is the seeing condition, and is related to the amount 

of natural and man made lighting available, and the contrast, reflectivity, and texture of surface terrain and 

obstruction features. In order to conduct operations safely, seeing conditions must be accounted for in the 

planning and execution of night VFR operations. 
Night VFR seeing conditions can be described by identifying “high lighting conditions” and “low lighting 

conditions.” 

1. 

High lighting conditions exist when one of two sets of conditions are present: 

(a) 

The sky cover is less than broken (less than 5/8 cloud cover), the time is between the local Moon rise 

and Moon set, and the lunar disk is at least 50% illuminated; or 

(b) 

The aircraft is operated over surface lighting which, at least, provides for the lighting of prominent 

obstacles, the identification of terrain features (shorelines, valleys, hills, mountains, slopes) and a horizontal 

reference by which the pilot may control the helicopter. For example, this surface lighting may be the result of: 

(1) 

Extensive cultural lighting (man

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made, such as a built

−

up area of a city), 

(2) 

Significant reflected cultural lighting (such as the illumination caused by the reflection of a major 

metropolitan area’s lighting reflecting off a cloud ceiling), or 

(3) 

Limited cultural lighting combined with a high level of natural reflectivity of celestial illumination, 

such as that provided by a surface covered by snow or a desert surface. 

2. 

Low lighting conditions are those that do not meet the high lighting conditions requirements. 

10

−

2

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8 

Special Operations