Timber Flashcards
What are the 3 formulas for all timber charges?
Internal: P=D^2/250
External: P=D^2/40
Abatis=P=D^2/50
P=lbs of TNT
D=diameter
What are the 3 considerations when targeting timber?
- Wind and Lean when determining direction of fall
- For unknown types of trees make a test shot to determine optimal size of charge
- Always attack the least dimension
What are the 3 types of timber explosives?
Internal, External and Ring
What formula do you use for a Ring charge?
External: P=D^2/40
What dimension do you want to attack on Dimensional timber charge?
Always attack the least dimension
What should be the width and thickness of a ring charge on a tree that is 15” thick or less?
As wide as possible, at least 1/2” thick
What should the width and thickness of a ring charge on a tree that is greater than 15” thick?
As wide as possible, at least 1” thick
For an Abatis obstacle what is the desired minimum length?
Ensure obstacle is at least 75 meters in length
Which direction should the fallen trees be facing?
3-5 meters apart and 45 degrees towards the enemy approach
What is the most critical factor for determining direction of fall?
Wind and the way the tree is leaning
How should holes in trees be drilled?
2” diameter, 2/3 deep
How can you influence the direction of fall?
1lb kicker charge, optimally placed 2/3 up the tree opposite of the main charge. Fired at the same time as the main charge.
What is the formula for an internal charge?
P=D^2/250
Dimensional timber’s have how many sides?
4 sides
How do you drill a circular timber if you have 2 holes?
90 degrees apart from each other with the desired direction of fall in between the 2 charges
How many forms attachment do you need for an explosive/charge?
2 forms of attachment
What formula do you use for Abatis?
P=D^2/50
On an Abatis how high do you place the charges?
5 feet above the ground
What is the minimum diameter for a tree when constructing an Abatis?
2 feet or 24 inches
When detonating the explosives for an Abatis construction what is the order you do it in?
Detonate one side of the road, let all of the trees fall then detonate the other side of the road and allow the trees to fall.
What does “most efficient/effective imply?
Internal charge, less explosives
What does work quickly imply?
External charge, more explosives
If time allows what do you want to do to prep the tree prior to emplacing charge?
Remove the bark
How do you calculate for diameter?
Circumference / Pi = diameter
What is the 6 step problem solving format?
1) all critical data
2) calculate for TNT (solve for P)
3) divide P/RE factor of explosives used
4) divide package weight and round up
5) determine # of targets
6) multiply # of targets by packages of explosives = total amount of explosives needed
External charge should be what size and shape?
Rectangular, 1-2” thick and twice as wide as they are high.
How do you calculate NEW for a block of explosive?
Qty x Package Weight x RE = Pounds of TNT
