( 

# Safety

Effects of Raising the Maximum Payload for Turboprop Aircraft
in Part 135 Cargo Operations

(

### THE ISSUE The FARs limit on-demand cargo operations

under Part 135 to aircraft with a maximum payload

of 7,500 pounds. This limits on-demand 135 cargo operators

to aircraft no larger

than the EMB-11

0 and the Beech-1900C. The Part 135 Advisory Rulemaking

Committee (ARC) recommends increasing

that limitation
to allow turboprop airplanes up

to a payload

of 18,000 pounds

to operate

ondemand cargo

services under Part 135. This captures

the following

fleet (mostly out-of-production): EMB-120 Shorts-360 ATR-42 ATR-72 Jetstream Saab 340 Fokker F.27 DASH-8

(1 00-300) BE-19000 YS-11 Convair 580

### The Rationale

- Efficiency The ARC believes the change

would fill a gap

in the cargo market,

as very

few aircraft between the BE-1900C

& the ATR-72 operate cargo flights

under Part 121. The ARC contends this is a consequence

of the regulatory structure: the targeted

fleet could operate

under Part 121, but acquiring

a certificate

is too time consuming

and too costly

to make that market niche attractive. As a result the targeted fleet is excluded from the cargo

market. Higher payloads might

also replace multiple,

smaller aircraft that operate simultaneously

on a route because

1 or even 2 aircraft cannot carry payloads

that markets demand.( 

### The Rationale

- Safety The ARC believes the change

also would improve safety

., as larger

and more powerful twin-turboprop airplanes

would have a lower accident rate than the fleet that currently operates cargo flights

under Part 135. This likelihood would be increased, according

to the ARC, by requiring

the targeted

fleet to meet selected requirements of FAR Part 121, but under an existing

Part 135 certificate. Advocates add that some Part 125 operators

have indicated that the proposed change

would be enough

to bring

**t~em** into Part 135, thereby adding

a presumed safety

beneiit.( The Safety

Question Posed by

the ARC The safety question posed by

the ARC is whethertwinturboprop airplanes

with payloads up

to 18,000 pounds,

with selected characteristics

of FAR Part 121, could operate under Part 135 with a lower accident rate than the current Part 135 cargo

fleet. The central conclusion

is less straightforward. • When assessed only against

the posed question,

the answer
is clearly "yes,

the targeted

fleet would have a lower accident rate than the current Part 135 cargo

fleet." • However,

FAA should address other questions

as well.

# Analysis of the Posed Question Nine key

characteristics

of the targeted

fleet were tested and scored against

230 

## Part 135 

## cargo airplane

accidents from 1998 

## through

2007. 

## The 230 

## accidents involved

a total of 234 

## Part 135 

## cargo

aircraft and 72 

## fatal accidents. Each of the 9 characteristics was assessed for the degree

to which

it likely

could reduce risk in each of the 230 

## cases based on the details of each accident. As in the VLJ analysis,

each characteristic was limited to a maximum score of 90°/o 

## against any single accident,

under the assumption

that risk can not be absolutely

eliminated. A simple

formula avoided double-counting against any single accident so that no accident was "saved" multiole times.( 

# Nine Key

Characteristics Based on ARC documents and conversations with some ARC members,

the following

characteristics were tested. • Require

a 2-person

crew. • Require Flight Following. • Require

an approved

Continuous Airworthiness Maintenance Program (CAMP). • Require

GPWS (future updates by

reference
to 121 ). • Require

TCAS (future updates by

reference
to 121 ). • Require Autopilot. • Require

On-Board Weather Radar (Updates by Reference). • Require

an approved pilot training program,

with simulators. • Assume the reliability, power



# & higher

altitudes available with twin turboprops.( 

## Some Analytical Challenges Many

of the characteristics lacked precision;

some of the precision

indicated on the preceding

slide was assumed by the team. For example, exactly

what is meant by

a "Part-121-like" approved

CAMP or "121-like" training?

What would be expected

of flight following?

Do we really

assume TAWS and On-Board Weather Radar (including retrofits)? Significant

variation

in the targeted

fleet made some cases difficult to score. When scored against

a particular

135 case,

the likely

outcome for an EMB-120
or BE-19000 might differ from the likely

outcome for an ATR-72-500
(or 600).

# G) CD 

# ::s CD


# .... D) 

# - m D) 

# )>Cl 

# n " 

# nee 

# -· .... c.o CD C: 

# ::s ::s

... c. tn 

# 0 

# ::s 

# -a D) 

# ::1All Accidents and Fatal Accidents,

Part 135 Cargo 1983-2007 70 **~----------------------------------~** 60 50 40 30 20 10 0 (Average 22 annually past 5 years) (Average

5 annually past 5 years) 83 85 87 89

91 93 95 97 99 '01 '03 '05 '07

### Airplane Accidents

& 

### Fatal Accidents,

Part 135 Cargo 1998-2007, Excluding Ramp

& Miscellaneous Events (Analytical Baseline) 70 **~------------------------------------~** 

### 60 **T--- --------------------------------~**  50 **T-**
**r- ------------------------------~**  

### 40



## I
**~.**



## , 30

:


# ~ 

# 1 ,-

**~** 1\
A



## I 20 **T-----------------------------**

**---- ~**  

### 10

I

'" **~**

,.. ........_

= ,......,.. ,........,_

I "'\:: ;,;.-

X :A:

I
.__

. 

### 0 **T-~~~~~~~~~~~~~~~~~~~** 83 85 87 89 91 93 95 97 99 '01 '03 '05 '07

# ., -· -·{

( 

### Percentage

of Risk Eliminated Targeted

Fleet Versus Actual Part 135 Cargo Accidents from 1998 to 2007 Ve rs us All A cci den ts

Ve
r sus Fatal A c cidents Alone Cum
Alone L.;um 2 Crew 13.4 13.4 GPWS 19.9 19.3 GPWS
12.1 24

. 8

2 Crew 18.8 36.4 T-Prop Eng

8

. 7 29.2 T-Prop Eng

15.3 46.8 Fit Follow

3.1 30.8
Fit Follow
4.4 48

. 8 CAMP

2.7 32.9 CAMP

3
. 1 50.1 Training

2

. 3 34.1 WX Radar

2

. 8 50.9 Wx Radar
2.2 34.9 Training

2.6 52

. 5 Auto-Pilot

0
. 6 35.3 Auto-Pilot

1
. 4 53.1 TCAS

0
. 4 35

. 6 TCAS

1
. 2 54.1 Most benefits come from 2 crew members, GPWS
& characteristics

of larger

twin turboprops (such as more power and higher altitudes)

.

(( 

### Background

on Part 135 Cargo

Accidents Alaska accounted for 53 of 230 accidents reviewed (23°/o)



### & 9 of 72 fatal accidents (12.5°/o). Of the 234 accident airplanes



### & 468 0-D locations: • 175 of 468 locations (37 .4°/o)

are non-towered • 11 °/o of locations have no published procedures • 74°/o have fuiiiLS. • A minimum of 34 accident 0-D pairs (15°/o)

are not potential markets for the targeted

fleet due to runway length,

remote sites, or extremely

short trips. • 43 Twin-Engine Turboprops

or Light

Jets (18°/o). • 33 Single-Engine Turboprops (14°/o). • 101 Twin-Engine Reciprocating Airplanes (42°/o). • 57 Single-Engine Reciprocating Airplanes (24°/o).