Gravity Circle
- Theoretical safety zone that surrounds the center of gravity on an aerial apparatus
PG 642
Post-Type Stabilizers
- AKA Downriggers
- Straight jacks that extend down from the chassis
PG 644
Box Stabilizers
- AKA H-Stablizers
- Stabilizers that extend straight away from the truck and have jacks that extend straight down to the ground
- Most common stabilizers used on newer apparatus
PG 644
A-Frame, Scissor, or X-Style Stabilizers
- AKA Fulcrum-Type Stabilizers
- Stabilizers that extend down and away from the chassis at an angle
PG 644
Stabilizers Shoe
Flat metal plate attached to the bottom of the aerial apparatus stabilizer to provide firm footing on the stabilizer surface
- AKA Stabilizer Boot or Stabilizer Foot
PG 652
Order of Deploying Stabilizers
- One stabilizer should never be activated alone
- Always activate in a multi-step, side-to-side or front-to-back process
- In a four-jack system, operate the stabilizers in parallel
PG 656
Short Jacking
- Partial extension of the stabilizer arms
- The load and range of save movement capabilities significantly decrease when extension arms are not fully extended
PG 658
Stabilizing on Uneven Terrain
1) Laterally:
- Correction of lateral unevenness is possible on grades of up to 5%/3 degrees (a slope that rises 5 feet for every 100 feet of distance)
- Lower stabilizers of uphill side first, then lower downhill stabilizers until they raise the downhill side of the truck is level with the uphill side
- Preferable to operate aerial device over the uphill side of apparatus
2) Longitudinally:
- Operate the aerial device either directly over the front or rear of the apparatus, depending on whether the apparatus stopped short of the objective or past it
PG 649-650
Steel Pins are used as a safeguard to prevent movement of the jacks for which type of stabilizer system?
Box
PG 662-663
What is the final step in engaging a PTO on an aerial apparatus equipped with an automatic transmission and no pump?
Shift transmission to neutral
PG 647
What is the maximum lateral grade that can be corrected with stabilizers?
5 degrees
PG 658
A hot shift PTO differs from standard PTO because the hot shift PTO can be engaged with the ________ ?
Main transmission in neutral
PG 646
Which type of stabilizer must be fully extended to be effective?
Fulcrum
PG 657
What problem is particularly severe when working on a longitudinal grade?
Higher lateral and twisting stresses on the aerial device
PG 659-660
When short jacking, the stabilizers should be fully extended on which side?
The same side the device will be extended
PG 658
When spotting a tractor-trailer aerial apparatus, maximum stability is achieved when the aerial device will be deployed _________ ?
Outside the angle created by the tractor and trailer
PG 665
When operating an aerial device with manual stabilizers, a stabilizer shoe lifts off the pad. What should be done?
Take no action
PG 664
