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Programme Air Transport Manual


b.  The location of the aircraft on the parking apron is important. The aircraft has to be easily accessibly by forklift, but should not be parked in the vicinity of passenger aircraft.

c.  The number of flights and estimated fuel consumption per day

should be discussed with the carrier. This will allow the CATO to make a
planning, not only for pallet production, but also for the filling of the
bags, the conditioning on the pallets and the loading in the aircraft.

d.  A list of required material for supporting the airdrop operations is in
Annex T. The dimension of the pallets should be verified with the Carrier
which should confirm the number of pallets required per MT of food.

e.  It will be required to have communications at the Dropping Zone

(DZ). The CATO should take the necessary steps to obtain the

authorization of the national authorities to use radios and the necessary frequencies to operate.

f. Airdrops are not authorized without the presence of a ground

controller at the Dropping Zone (DZ). The CATO should take the

necessary steps to recruit the required experts or qualify staff members for performing this function.

7.13.3. DROPPING ZONE (DZ) General

a.  Normal in-flight food dropping implies a geographically suitable DZ,
an obstacle free approach and sufficient airspace to manoeuvre the
aircraft into the dropping position. In addition, the area behind the DZ
should be kept clear because a late drop due to human error or
technical failure could have disastrous consequences. The DZ should
be away from buildings, village centres or any area where it is difficult to
police the zone. In all cases, it should be avoided to have built-up areas
(houses, villages) in the axis of the dropping direction, in front off and
beyond the DZ.

b.  Dropping zones should be selected, either in function of the

prevailing wind or, if the wind is not a prevailing factor, have a

North/South orientation. The latter will prevent that the pilots have to

drop into the sun in the morning or late afternoon. On the other hand, if the aircraft can drop in headwind conditions, the lateral drift will be
minimal and the horizontal impact speed of the parcels will reduce
proportionally and thus causing less damage. Criteria and Dimensions

a.  Such as depicted in figure 7.3, the dimensions of the DZ vary with the aircraft type. DZ itself is a well delineated zone that should be cleared of major obstacles and large stones, surrounded by a safety zone. The C 130 or AN 12 normally drop from an altitude of 700 feet, the IL 76 from 1000 feet.

b.  For Hercules, the length of the DZ should be at least 600 meters and the width 130 meters. For IL 76, minimum length should be 1000 m and the width 200 meters.


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c.  The safety area is an area of 200 m around the perimeter of the DZ. The  area  behind  the  DZ  should  preferably  be  longer.  In  ideal circumstances there should be no habitation in the zone extending 1500 meters behind the centre of the DZ.

d.  The ideal surface would be of supple consistency whether earth, grass  or  sand.  Hard  surface  provokes  a  hard  shock  on  impact. Especially rocks cause total havoc. On the other hand, providing the DZ is accessible by trucks, soft surfaces are ideal for air drops.




Keep free for at least
1500 metres













>200 m >200 m


130 (200) m


• Distances are in metres

• The figures between brackets
are for IL 76

Figure 7.3.




e.  Maximum effort must be made to present the DZ to the pilot as easy
and "eye-catching" as possible. Therefore, markers will be placed at
pre-determined places. Markers can be made from white food bags,
sewed double-width for better visibility. If no food bags are available or
in emergency, other tools such as plastic fire ash or smoke can be
used. The markers can be put on the ground and secured by stones or
other heavy material.



















Figure 7 - 4



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f. Figure 7- 4 shows the typical placement of the markers to designate

the dropping zone to the aircrew.

g.  A white cross (1.5 meter width, 10 meter axis) should indicate the centre of the DZ, the longest axis aligned with the run-in heading. The corner markers should be put up at the 4 corners of the DZ. The dropping direction should be indicated by either;

At least 2 line-up banners (1.5 meter width, 10 meter length and 3 meter height, one at the beginning of the DZ, the second at the end of the DZ, aligned with run-in heading and the centre cross, or

A  white  arrow  just  before  the  dropping  zone,  pointing  in  the dropping direction towards the white cross.

h. A zone of at least 1500 meters behind the centre of the DZ should
be prohibited for people and/or domestic animals.

7.13.4.  PATTERNS

a.  A typical pattern for C 130 is depicted in figure 7.5. The initial part of the approach to drop consists of a down-wind leg, i.e. with the wind from the back. Its course is parallel to the dropping area in the opposite direction. On this course, speed is reduced in order to allow the opening of the ramp door and setting the flaps.

b.  Altitude is 1000 to 2000 feet above ground. On the end of this down
wind leg follows a shallow turn of 180 o , shallow because of low speed and
pallets with sacs which slip in steep turns. For this turn, a space of at least
2 NM (3.7 km) is required. With strong cross winds, an even larger distance
is needed to compensate for the drift. During the last part of the final turn
the plane descends to its dropping altitude and starts the final approach.
For allowing proper line-up during the final approach, the crew must identify
the DZ during the base leg turn.

c.  Holding patterns shall be flown at minimum 3000 feet above ground level and/or minimum 2000 feet vertical separation between the aircraft in the dropping pattern and the holding aircraft.







2-3 NM


Final Approach










Air Release





2000 m

Approach Clearance



500 m 500 m

Dropping Zone



2000 m

Evacuation Zone

Figure 7 - 5

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d.  Once in final the pilot should acknowledge that he/she has the DZ in sight and confirm the dropping heading.

e.  Figure 7 - 5 also depicts the final approach of an IL 76. The aircraft
stabilizes at its release altitude well before the release point. This release
point should always be located within the boundaries of the dropping zone.
Since the release speed and altitude of the IL 76 are higher than for the C
130, the IL 76 release point will be further away from the white cross.
Hence the requirement to have a larger dropping zone for the IL 76.

f. After release, the aircraft should continue on the same heading until the
load is fully cleared and the doors are closed.


a.  Once the decision for air dropping has been taken, it is necessary to contact local authorities in order to obtain permission to operate a mobile aeronautical ground station with its usual VHF frequencies ranging from 117 to 144 MHz. In most cases, it is the Ministry of Foreign Affairs, Ministry of Defence or State Security and certainly the Post & Telecommunication and Civil Aviation Authority who issue these permits.

b.  WFP AFO should have its own supply of such VHF air-band

transceivers. They should be battery operated and independent from any
power supply but need to be recharged overnight from a 220 V source. A
small generator or a solar panel set is quite sufficient for this task. If
equipped with a small whip antenna, additional installations are
unnecessary to give the necessary range of 30 to 50 km depending on the
terrain. It must be borne in mind that VHF works on a "line of sight" basis
and can therefore become very limited as soon as there is an obstacle in
between, like a mountain.

c.  Ascertain that the elected frequency with is not in use in the country to avoid unwanted interference which might lead to serious consequences and finally to withdrawal of permission. The person operating this
aeronautical VHF radio must not only be in possession of a general Radio Operators licence but also be the holder of an aeronautical radio operator’s licence. Do not attempt under any circumstances to contact the tower or aircraft in flight working directly on any tower frequency.

d.  Preferably, the ground controller should also have a portable HF

system, not only as back-up for the VHF, but also to be able to talk to the home station and be kept informed of any changes in the schedule.

7.13.6.  RADIO PROCEDURES General

Proper radio communication is the most important factor in conducting
a safe airdrop.  Two-way VHF radio contact is mandatory for performing
the drop. Performing airdrops with only HF radio contact is not

  Terminology must be clear and concise.

  The use of standard terminology will avoid misunderstandings.

   Always use the phonetic alphabet in radio communications.

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  Use the complete call signs of both the ground station and the
aircraft. This is especially important when multiple aircraft and/or
multiple ground stations are working on the same frequency.

  The DZ Controller must assure that all transmissions (reference are acknowledged by the PIC. If no response is received
within 5-10 seconds, the DZ Controller will repeat the transmission Initial contact

   The DZ monitor should announce his position in relation to the DZ.

   The DZ monitor will inform on the local weather conditions, including the wind direction and the estimated velocity.

   The Pilot in Command (PIC) will announce the type of drop (1, 2 or more runs) and give details on the type of cargo. Mandatory calls

   PIC calls 10 minutes prior to drop

   PIC calls 3 minutes prior to drop

   PIC calls 1 minute prior to drop.

   DZ controller gives clearance to drop. Terminology

Following terminology is mandatory and should be repeated by the

other party; e.g. after the ground controller announced “clear to drop”, the PIC should repeat “clear to drop”.

   Dry run” - The PIC reports that there will be no dropping during the
overflight of the DZ.

“Live run” - the PIC announces that it is his intention to drop his

cargo during the next run. This should be announced when calling 3 minutes prior to drop.

“Clear to drop” Confirmation by the DZ controller that the aircraft is
clear to drop. This clearance should be given when the PIC calls at
3 minutes prior to drop and confirmed at the 1-minute call.

“Negative drop” or “Not clear to drop” The DZ controller does not

give the clearance to drop.

“Abort, No drop”- Announcement by the DZ controller that, after the

initial clearance to drop, the zone is unclear for any reason. The

pilot should acknowledge and repeat this call abort the drop.

“Stand by for clearance”- Announcement by the DZ controller to

hold until the clearance is given.

“Committed” PIC informs that the drop cannot be recalled.

“Confirm”- Asking for confirmation of last given message.




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7.13.7. AIR/GROUND SAFETY General

   Safety is the most important aspect of all aviation operations. Although it is the responsibility of the Pilot in Command (PiC) to judge on the fulfilment of all safety criteria for accomplishing the mission, the ground controller should provide all available information for assisting the PIC in his/her judgement.

   Bear  in  mind  the  attitude  of  the  local  population.  All possible precautions around the DZ should be taken. This can be done by putting guards around the DZ. Make sure that security is in place at least one hour before the scheduled drop. Everybody should evacuate outside the safety zone. The drop should be cancelled if no security personnel were available. Air Safety

  All relevant aviation rules and regulations will apply. This implies that, except for dropping purposes, the aircraft will not be allowed to descend  below  the  minimum  altitudes  described  in  the  national regulations.  In  no  case  shall  the  ground  controller  be  allowed  to overrule these regulations.

  Successive droppings by different aircraft should be separated by at
least 5 minutes.   Although pilots are responsible for traffic separation,
the ground controller will inform both the leaving and arriving aircraft of
their respective positions and intentions and will assist with traffic

  If dropping is still in progress when the next aircraft arrives, the
arriving aircraft will proceed to the holding pattern. Holding altitude will
be at least 3000 feet above ground level and the holding fix will be the
DZ. Normally, holding patters are done to the right with one minute

  If  the  airdrop  is  performed  in  the  vicinity  of  an  active  airstrip; following rules will apply:

- Traffic separation is a responsibility of the PiC involved

- Airdrops have priority over landing or take-off, except if the

landing strip is also used as DZ or if it is felt that the DZ is too close for safe dropping. If the latter is the case, the landing strip should be cleared before dropping.

  If the ground controller judges that the circumstances may lead to a
dangerous situation, he/she should take action accordingly and warn
the PiC.

  It should be noted that the PiC needs at least 15 seconds to comply with an abort. Ground Safety


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