Part 137 AG Overload History Legal load for a Fletcher 400 in the - - PDF document

Part 137 AG Overload

History

• Legal load for a Fletcher 400 in the

70s and early 80s was approx .9 of a tonne using the gross weight of 5430 lbs Cresco was approx 1.7 tonnes

• Other aircraft types equally affected

Agwagon Agcat Thrush etc

• Every body operating illegally with

typical Fletcher loads of 1 to 1.2 tonnes

Adoption of CAM 8

• Approach made to Airworthiness Division of CAA to adopt

world wide industry practice of allowing the use of CAM 8 an American rule that recognizes a trade off between increased weight and the allowable operating parameters as published in the aircraft flight manual to determine a new safe all up weight.

• The method of deducing the weight allowed was to use a

graph published in CAM 8 that took into account the

• riginal airplane limit load factor and applying this

percentage increase to the standard category weight.

• It worked well for the industry and legitimized

what was standard practice over the years.

• It has not resulted in any increase in the accident
• rate. The real safety issue of overloading is that of
• verloading for the conditions. Rough

strips/wind/turbulence

• It has not resulted in any increase in structural

problems with the aircraft used in the industry.It is most probably the operation outside of the parameters that will or may cause the damage.

• Then we had the advent of larger numbers of

higher horsepower and better performing aircraft.

• They in one respect made the job safer providing

increased performance but in other respects now

• pened up the opportunity to exceed the

provisions of CAM 8. Just like a Porche will do 300 K but the roads wont allow.

• Discipline is required to operate within the weight

limitation.

• The rules did not have the other conditions re the

need for reduced speeds whilst operating within the increased weight allowance.

• CAA expressing concern re the provision and the

fact that the other factors were not published.

• Industry urged CAA to write an AC to

explain and educate re the need to embrace all of CAM 8 rather than just the weight increase.

• To remove the provision from the rule

would be very retrograde and drive the industry back to blatant lawlessness.

• To stop this happening we must reassure the

regulator that we are responsible and ensure we do not overload beyond the provision.

• Speeds
• Va Vno
• G forces
• 4860 lbs X 3.8 = 18468 lbs
• 6366lbs X 2.9 = 18461 lbs
• Jettison capability
• Performance
• HP and Torque

Air Speed Limitations

The bend @ 27000 lbs

The ripples @27000 lbs ultimate=12.36 tonnes

• AC required
• Tidy up the rule insert the limitations
• Change the word overload to increased all

up weight allowance as provided for in CAM 8

• If manufacturer will not produce the

performance graphs and limitations then we the industry should do it for each type.