Showing posts with label vehicle. Show all posts
Showing posts with label vehicle. Show all posts

Sunday, March 31, 2019

OWB Air Combat: American Planes



https://theosrlibrary.blogspot.com/2019/03/operation-white-box-wwii-air-combat.html
American planes used in Europe and the Pacific theatres.

American Fighters/Fighter-Bombers
P38 Lightning
Saw service in Europe and most extensively in the Pacific. The P-38 was used for interception, dive bombing, level bombing, ground attack, night fighting, photo reconnaissance, radar and visual pathfinding for bombers and evacuation missions, and extensively as a long-range escort fighter when equipped with drop tanks under its wings. It can be fitted with rockets and bombs.
AC: 5 [14]
HP: 20 (HD 4)     
Move: 9/41 flying, +7 airspeed bonus
Attack: All [operator-linked]
x4 fire-linked .50 Large MG (+2 hit, 2d6+2), nose
1 20mm Medium Autocannon (2d6+2), nose
Mods: Aerial, Communications
Country: USA
Year: 1939
Crew: 1
Range: 2237 miles
Ceiling: 43.963'
Climb: 2500' per minute

P-40 Warhawk
The most common type of fighter in the U.S. Army Air Corps (USAAC) when the United States entered the War. The Lockheed P-38 Lightning could outperform the P-40, especially at high altitude, but the tough P-40 was less expensive, easier to build and maintain, and was in large-scale production at a critical period in the nation’s history when fighter planes were needed in large numbers. The solid, reliable Warhawk was used in all theatres and some were sent to Russia. Can be fitted with bombs.
AC: 4 [15]
HP: 24 (HD 4)     
Move: 9/38 flying, +6 airspeed bonus
Attack: All [operator-linked]
x6 fire-linked .50 Large MG (+3 hit, 2d6+4), wings
Mods: Aerial, Communications
Country: USA
Year: 1941
Crew: 1
Range: 240 miles
Ceiling: 38,156'
Climb: 2142' per minute


P-47 ThunderBolt
Used as both a high-altitude escort fighter and a low-level fighter-bomber, the P-47 quickly gained a reputation for ruggedness. Its sturdy construction and air-cooled radial engine enabled the Thunderbolt to absorb severe battle damage and keep flying. During WWII, the P-47 served in almost every active war theater and in the forces of several Allied nations. The most important U.S. fighter in Europe by the end of the War, outnumbering P-38 Lightnings and P-51 Mustangs combined. Can be fitted with rockets and bombs.
AC: 4 [15]
HP: 22 (HD 4)     
Move: 9/43 flying, +7 airspeed bonus
Attack: All [operator-linked]
x8 fire-linked .50 Large MG (+4 hit, 2d6+6), wings
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 1
Range: 449 miles
Ceiling: 40,994'
Climb: 3200' per minute


P-51 Mustang
The Mustang was among the best and most well-known fighters used by the U.S. Army Air Forces during World War II. Possessing excellent range and maneuverability, the P-51 operated primarily as a long-range escort fighter and also as a ground attack fighter-bomber. The Mustang served in nearly every combat zone during the War. It could be fitted with rockets and bombs.
AC: 5 [14]
HP: 22 (HD 4)     
Move: 9/44 flying, +7 airspeed bonus
Attack: All [operator-linked]
x4 fire-linked .50 Large MG (+2 hit, 2d6+2)
x4 fire-linked 20 mm Medium Autocannon (+2 hit, 2d6+4)
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 1
Range: 851 miles
Ceiling: 41,900'
Climb: 3475' per minute


F4U Corsair
Navy and Marine fighter/bomber. It was tough, fast, and well armed. Corsairs were used in the Pacific. An alternate armament was x4 fire-linked 20mm cannons and could be fitted with two 1,000 lb bombs or eight 5 inch rockets.
AC: 4 [15]
HP: 20 (HD 4)     
Move: 9/45 flying,  +8 airspeed bonus
Attack: All [operator-linked]
x6 fire-linked .50 Large Machinegun (+3 hit, 2d6+4)
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 1
Range: 1005 miles
Ceiling: 41,339'
Climb: 4360' per minute


Grumman F4F Wildcat
The main Navy fighter at the start of the War it was outclassed by the Zero. Saw extensive action in the Pacific Battles of the Coral Sea and Midway. It was replaced by the Hellcat in 1943. It could be fitted with two 250 lb bombs.
AC: 5 [14]
HP: 15 (HD 3)     
Move: 9/33 flying,  +5 airspeed bonus
Attack: All [operator-linked]
x4 fire-linked .50 Large Machinegun (+2 hit, 2d6+2)
Mods: Aerial, Communications
Country: USA
Year: 1940
Crew: 1
Range: 900 miles
Ceiling: 34,698'
Climb: 2000' per minute


Grumman F6F Hellcat
Designed to counter the Zero it replaced the Wildcat in 1943. It had a high rate of climb, good dive speed, armor, and weapons and yet was maneuverable. It could be fitted with a variety of rockets and bombs.
AC: 5 [14]
HP: 22 (HD 4)     
Move: 9/39 flying,  +6 airspeed bonus
Attack: All [operator-linked]
x6 fire-linked .50 Large Machinegun (+3 hit, 2d6+4)
Mods: Aerial, Communications
Country: USA
Year: 1943
Crew: 1
Range: 944 miles
Ceiling: 37,300'
Climb: 3400' per minute


Douglas SBD Dauntless
The Navy's standard ship-based dive bomber in the Pacific, they were also used as land based bombers by the Marines. They carried the victory at the Battle of Midway sinking four Japanese aircraft carriers, crippling their fleet. A rugged plane with good defensive firepower.
AC: 4 [15]
HP: 24 (HD 4)     
Move: 9/26 flying,  +4 airspeed bonus
Attack:
x6 fire-linked .50 Large Machinegun (+3 hit, 2d6+4), nose, [operator-linked]
x2 fire-linked .30 Medium Machinegun (+1 hit, 1d6+3), dorsal turret, gunner
2,000 lbs of bombs
Mods: Aerial, Communications
Country: USA
Year: 1938
Crew: 2 (pilot, gunner)
Range: 1,115 miles
Ceiling: 25,525'
Climb: 1700' per minute


Grumman TBM Avenger
Designed to replace the obsolete pre-War Devastator. It carries bombs or a torpedo in an enclosed bay. It is bristling with defensive machine guns. Only one of six deployed survived the battle of Midway, but despite this the Avenger became the Navy's main torpedo plane.
AC: 4 [15]
HP: 22 (HD 4)     
Move: 9/27 flying,  +4 airspeed bonus
Attack:
x2 fire-linked  .50 Large Machinegun (+1 hit, 2d6+1), [operator-linked]
x1 .50 Large Machinegun (2d6), rear turret, gunner
x1 .30 Medium Machinegun (1d6+2), ventral, torp officer
2,000 lbs of bombs or torpedo
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 3 (pilot, gunner, torpedo officer)
Range: 1,215 miles
Ceiling: 22,402'
Climb: 2060' per minute


BOMBERS
Boeing B-17 Flying Fortress
Nicknamed the Flying Fortress the B-17 was the most famous bomber of the war having seen action in every theater. It could sustain heavy damage and keep flying. It bristled with .50 machineguns and was most used for daylight bomb raids to avoid as many civilian casualties as possible. This policy cost a lot of airmen's lives.
AC: 3 [16]
HP:   48 (HD 8)   
Move: 9/28 flying, +4 airspeed bonus
Attack:
x2 fire-linked .50 Heavy Machinegun (+1 hit, 2d6) in 9 positions (2 in the Bendix chin turret, 2 on nose cheeks, 2 staggered waist guns, 2 in upper Sperry turret, 2 in Sperry ball turret in belly, 2 in the tail and one (2d6) firing upwards from radio compartment behind bomb bay) all gunner positions
Bombs: 8ooo to 17,600 lbs.
Up to 3 gunners can target one aircraft from the firing arcs
Mods: Aerial, Communications
Country: USA
Year: 1937
Crew: 10 (pilot, co-pilot, navigator, bombardier/nose gunner, flight engineer/top turret gunner, radio operator, waist gunners (2), ball turret gunner, tail gunner)
Range: 2001 miles
Ceiling: 35,600'
Climb: 540' per minute

Douglas A20 Havoc
Light bomber, attack, and night-fighter aircraft. It was one of the first American aircraft to serve in the War. It was said to be easy to fly and handled well. It was also a stable gun-platform for night-fighter missions. A sturdy, tough, well designed plane. Can be fitted with up to 4,000 lbs of bombs.
AC: 4 [15]
HP: 25 (HD 5)   
Move: 9/34 flying, +5 airspeed bonus
Attack:
x6 fire-linked .50 Heavy Machinegun (+3 hit, 2d6+4), Nose [operator-linked]
x2 fire-linked .50 Heavy Machinegun (+1 hit, 2d6), rear turret, gunner
Mods: Aerial, Communications
Country: USA
Year: 1941
Crew: 3 (pilot, co-pilot, gunner)
Range: 1091 miles
Ceiling: 25,098'
Climb: 1500' per minute

Douglas A-26 Invader
Medium bomber and heavy attack aircraft. It is a tougher, faster, and better armed option to the A20. In the summer of 1945 the armament was upgraded for its ground attack roll to 8 firelinked Heavy Machine Guns on the nose (+4 hit, 2d6+6, 150') and 6 firelinked Heavy Machine Guns in the wings, 3 per wing ((+3 hit, 2d6+4).
AC:  4 [15]
HP:   30 (HD 6)   
Move: 9/35 flying, +6 airspeed bonus
Attack:
  x6 fire-linked .50 Heavy Machinegun (+3 hit, 2d6+4), Nose [operator-linked]
x2 fire-linked .50 Heavy Machinegun (+1 hit, 2d6), Dorsal turret, gunner
x2 fire-linked .50 Heavy Machinegun (+1 hit, 2d6), Ventral turret, gunner
x10 Rockets (5 per wing)
Bombs: 6000 lbs
Mods: Aerial, Communications
Country: USA
Year: 1944
Crew: 3 (pilot, 2 gunners)
Range: 1300 miles
Ceiling: 22,100'
Climb: 1250' per minute

OTHER
Douglas C-47 Skytrain
One of the main transport planes of the allies. It can carry up to 6000 lbs  of cargo or 28 troops. 50k paratroopers were dropped over Normandy from Skytrains. The plane could be fitted with cargo doors, hoists, and even mooring for gliders. It is unarmed.
AC: 6 [13]
HP:  30 (HD 5)   
Move: 9/22 flying, +3 airspeed bonus
Attack: All [operator-linked]
None.
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 4 (pilot, co-pilot, navigator, radio operator)
Range: 1600 miles
Ceiling: 24,000'
Climb: 1041' per minute


Monday, March 11, 2019

Operation Whitebox vs DC: The War Wheel

Rolling death from DC WWII war comics....

THE WAR WHEEL
Ultra-Heavy Rolling Tank
ARMOR CLASS 3 [16]
HIT POINTS 120 (HD 20)
MOVEMENT 18 (L150 x W150)
ATTACK x2 Heavy Tank Gun (F), x2 Heavy Tank Gun (R), x5 Heavy Tank Gun (L), x5 Heavy Tank Gun (R)
MODIFICATIONS Communications, Firing Port x3 (14 Heavy Tank Guns), Reinforced Hull (x6, 0 damage from Heavy Weapons due to mass and armor), Supercharged Engine

SPECIAL
Crush -
The War Wheel's spiked exterior is made to crush and roll over enemies. It does x6 damage to objects it is rolling over and with it's Reinforced Hull x6 it takes no damage from anything less than another ultra-heavy vehicle or objects (at the War Master's discretion.) It's crew take no damage in a collision unless the War Wheel is actually damaged in a collision.

Vehicle Mishap (OWB Tactical Combat, pg 33)
Due to its gyroscopic design and size the War Wheel ignores the Roll Over result. Roll again.
If a raiding party manages to destroy the gyroscopic mechanism from within, the War Wheel may fall on its side if the Roll Over result comes up.

History
A massive Nazi super weapon crewed by 22 men: fourteen gunners, two drivers, four technicians, a Sgt, and a Captain (Commander.)

The dreadnaught is 150' in diameter and covered in massive spikes. It is incredibly armored and can survive artillery fire. It is vulnerable to bogging down in wetlands.

The first Wheel also had another flaw: electricity. If coming into contact with power lines or other major electrical source the crew  will suffer 4d6 damage, Save for half. Later Wheels were insulated against this.

If a squad can get on the Wheel and inside they can shoot their way through several levels of the goliath machine.

Another adventure would be the Allies creating an ultra-damage weapon to do full damage and the squad having to bring it, position it, attack, etc.


Friday, March 8, 2019

Operation White Box WWII: Air Combat Options, Planes, Flyboy Class



Almost finished with this one. Need to finish a few airplane stats (mostly German and Japanese), work over some Flak and Bombing Rules and reconsider the final ability of the Flyboy class.
So a mostly finished post. A work in progress. I'll re-up it with pics when I get done.
But for now............

EDIT:
Cleaned up the post, modified a few small rules, finished the Flyboy class.
More planes (especially enemy and bombers), flak rules, and bomb rules on the way soon.

DAVE'S OWB WWII AIR COMBAT
Combat Proceeds As:
1. Spot Foe
2. Maneuver Roll
3. Initiative
4. Movement
5. Attacks, etc

SPOT FOE
Normal Ambush/surprise checks with bonus/penalty as applied by the War Master.
Came out of the sun, came from behind, etc.

MANEUVER ROLL
This is an opposed Piloting check (Dex checks + bonus from the Death from Above ability) between Flyboys involved in battle.

The Flyboys are dog-fighting and doing other combat tricks to gain the advantage.
A Flyboy must make their check by rolling their Dex score (+ bonus) or less on a 1d20. If both make their check whomever made by the most wins.

  • The winner has maneuvered into an advantageous position over his foe and gets a +2 to hit and +2 to Initiative bonus until the beginning of the next round. He also receives  a +2 bonus to his Piloting Maneuver roll the next round.
  • A tie equals no bonus to either Flyboy.

For Example: 
A 1st level Flyboy with a Dex of 14 (and a +1 Death from Above bonus for a total of 15) runs into combat with a 3rd level Flyboy with a 14 Dex (and a bonus of +2 for a total of 16.)  Both roll. The 1st level Flyboy rolls an 8, the 3rd level Flyboy rolls a 12.

The 1st level Flyboy made his roll by 7, the 3rd level Flyboy made his by 4. The 1st level Flyboy gains the Maneuver bonuses this round and has a +2 to initiative next round.

Not every pilot in the sky is a Flyboy.
If a pilot flying an aircraft is not of the Flyboy class their maneuver roll is at a -4 penalty.

INITIATIVE
Normal 1d6.
+2 bonus for a Flyboy's All in the Reflexes ability.
+2 if a Maneuver roll was won the previous round.

MOVEMENT
Movement is tracked  with normal OWB rules. The following applies in combat:
The loser of Initiative moves first to allow the Maneuver winner to see where the loser places his plane and then place his own plane.

AC Bonus and Air Speed
Airplanes move a LOT faster than ground vehicles, often going hundreds of miles per hour. Unlike ground vehicles where you multiply the speed by yards x 10 (or 30'), with aircraft you multiply the aircraft speed by yards x 30 (or 90') to get it's movement in feet per round.
https://www.militaryfactory.com/aircraft/ww2-aircraft-ranked-by-speed.asp

Their speed also makes them harder to hit.

Speed Categories
Current Speed AC Bonus
10 +1
15 +2
20 +3
25 +4
30 +5
35 +6
40 +7
45 + +8

In a plane vs plane combat the speed AC bonus of a slower flying plane subtracted from the bonus of a faster flying plane. The remainder is added as an AC bonus to the faster plane. (The faster plane is better but doesn't completely overwhelm it as it does a ground target.) A P-51 going all-out vs a Messerschmidt 110 going all- out has a +1 AC bonus (7 -6 = 1.)

When speed is reduced either by choice or damage use the lower speeds bonus.

ATTACKS, ETC
Armor Class
Vehicle AC
+ Dex bonus
+ Speed Factor
+ bonus from Flyboy Ace ability
+4 Flying defensively (no attack attempt)

To Hit
Normal 1d20 plus pilot's Ranged Hit
-2 non-Flyboy or Grunt class
+2 maneuver bonus if gained
+ linked weapon bonus if applicable

Damage to Aircraft
1. IF aircraft is at half Hp's or less, -4 to Piloting rolls.
2. When at half Hp's or less every damaging hit is a critical hit.
3. A natural 20 is a critical hit.

Roll 1d6.
On a 1-4:  an engine/critical system hit. See engine criticals below.
On a 5-6:  1d3 crew are hit. Save for half damage.

Aircraft at 0 hp or less, roll a 1d6. On a 1 it explodes for 6d6 damage. On a 2 it bursts into flame causing 1d6 per round to crew. On a 3-6 it falls from the sky trailing smoke and impacting in 1d4 +2 rounds.

Targeting the Engine or Pilot
-6 to attack the engine or cockpit/crew (due to position and better armor at these locations.)
See Engine/Critical System damage below.

Engine/Critical System
  • x2 damage.
  • The total damage done  is the percentage chance on a 1d100  that the plane's performance is impacted. Roll for each successful attack successfully.
  • IF this roll is successful drop speed by 1/4 of full speed on the first hit.
  • Each additional hit and successful percent roll drops the speed by another 1/4 of full speed until the plane reaches 0 speed and falls from the sky.
Stalling
IF a natural 1-5 percent is rolled on any of the engine/critical system percentile rolls the engine stalls and the plane begins to fall from the sky.
  • The Pilot must make an Int check (+ Pilot bonus) - total engine damage to restart it.
  • The Pilot has 1d4 +2 rounds to get restart or get out.

Linked Weapons
Multiple machineguns liked to fire at the same time and same target. Each extra weapon gives a bonus to hit or damage as seen on the chart below. If more than one caliber of weapon is linked choose the highest damage for the base damage. Remember: the guns fire three times per combat round.

Linked Weapons
2 guns  +1 hit
3 guns  +2 dmg
4 guns  +2 hit/+2 dmg
5 guns  +2 hit/+4 dmg
6 guns  +3 hit/+4 dmg
7 guns  +3 hit/+6 dmg
8 guns  +4 hit/+6 dmg

Autocannon
Autocannon, small 15mm 2d6
Autocannon, medium 20mm 2d6+2
Autocannon, large 30mm 3d6
vs Personnel: Explosive Radius 30'

Airplane Bursts
Three attacks per round, 10 bullets per weapon per burst.
 The pilot can choose to use only one or two bursts to conserve ammo.

Rockets
Airplanes equipped with rockets under their wings were great at knocking out enemy armored vehicles and other hard targets.

Treat the rockets as a Heavy RPG  (8d6 damage) with a 200' range increment.
They can be fired in pairs or even larger groups of four, six, etc. Treat bonuses to hit and damage as if fire-linked. Two rockets fired would be a +1 to hit, 4 would be a +2 hit/+2 dmg, etc.

AC Bonus and Air Speed
Airplanes move a LOT faster than ground vehicles, often going hundreds of miles per hour. Unlike ground vehicles where you multiply the speed by yards x 10 (or 30'), with aircraft you multiply the aircraft speed by yards x 30 (or 90') to get it's movement in feet per round.
Their speed also makes them harder to hit.

Speed Categories
Current Speed /AC Bonus
10 +1
15 +2
20 +3
25 +4
30 +5
35 +6
40 +7
45 + +8

In a plane vs plane combat the speed AC bonus of a slower flying plane subtracted from the bonus of a faster flying plane. The remainder is added as an AC bonus to the faster plane. (The faster plane is better but doesn't completely overwhelm it as it does a ground target.) A P-51 going all-out vs a Messerschmidt 110 going all- out has a +1 AC bonus (7 -6 = 1.)

When speed is reduced either by choice or damage use the lower speeds bonus.

Alternate Strafing Run
Operation Whitebox gives rules for Strafing Runs on page 59.
As an alternate system we can use the Speed AC Bonus above:
A soldier on the ground is firing at a P-51 mustang. The AC of the plane receives a +7  bonus as it roars by at over 400 mph bumping its AC up to  20 + the Pilot's Dex bonus + his Death From Above bonus.

Unfortunately for the pilot it is harder to hit man-sized targets while you're roaring through at 400+ mph. Using all three Machine Gun attacks per each set of available linked weapons allows the Pilot attack an area 30' wide by a number of feet equal to current airspeed. Everyone in this area is rolled against as possible targets but get a bonus to AC equal to the plane's current airspeed bonus plus a cover bonus if they are under partial or soft cover and the War Master rules they can be hit.

Our soldier above who fired at the P-51 gets a +7 to his AC bonus against the plane and since he is standing behind a brick barricade the War Master gives him a +4 cover bonus for a total of +11 to his AC vs the plane.

Airplane Profiles
Generic Small Plane (via OWB)
AC: 7 [12]
HP:  12 (HD 3)     
Move: 9/36, +6 airspeed bonus
Attacks: Medium Machine Gun (x2) [operator-linked]
Mods: Aerial, Communications
Country: Any
Year: late 1930's
Crew: 1
Range: 1000 miles
Ceiling: 27,000'
Climb: 2000' per minute


P38 Lightning
AC: 13
HP: 18 (HD 3)     
Move: 9/41 flying, +7 airspeed bonus
Attack: All [operator-linked]
x4 fire-linked Large Machine Gun (+2 hit, 2d6+2)
1 medium Autocannon (2d6+2)
x10 Rockets
Mods: Aerial, Communications
Country: USA
Year: 1939
Crew: 1
Range: 2237 miles
Ceiling: 43.963'
Climb: 2500' per minute


F4U Corsair
AC: 13
HP: 15 (HD 3)     
Move: 9/42 flying,  +7 airspeed bonus
Attack: All [operator-linked]
x6 fire-linked Large Machine Gun (+3 hit, 2d6+4)
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 1
Range: 1016 miles
Ceiling: 36,909'
Climb: 3000' per minute


P-40 Warhawk
AC: 13
HP: 15 (HD 3)     
Move: 9/42 flying, +7 airspeed bonus
Attack: All [operator-linked]
x6 fire-linked Large Machine Gun (+3 hit, 2d6+4)
Mods: Aerial, Communications
Country: USA
Year: 1941
Crew: 1
Range: 240 miles
Ceiling: 38,156'
Climb: 2142' per minute


P-47 ThunderBolt
AC: 13
HP: 15 (HD 3)     
Move: 9/43 flying, +7 airspeed bonus
Attack: All [operator-linked]
x8 fire-linked Large Machine Gun (+4 hit, 2d6+6)
x10 Rockets
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 1
Range: 449 miles
Ceiling: 49,994'
Climb: 3200' per minute


P-51 Mustang
AC: 13
HP: 15 (HD 3)     
Move: 9/44 flying, +7 airspeed bonus
Attack: All [operator-linked]
x4 fire-linked Large Machine Gun (+2 hit, 2d6+2)
x4 fire-linked Medium Autocannon (+2 hit, 2d6+4)
Mods: Aerial, Communications
Country: USA
Year: 1942
Crew: 1
Range: 851 miles
Ceiling: 41,900'
Climb: 3475' per minute

FLYBOY CLASS
Identical to Wheelman with the following Class Abilities:

Death from Above
A Flyboy adds a +1 bonus to Piloting (Dex) checks at first level. The bonus increases to +2 at third level and +3 at fifth level.

This applies to all Piloting checks called for by the War Master but will be most useful in combat as it will help win the opposed Piloting check at the beginning of Airplane combat rounds for the +2 Maneuver bonus.

This bonus also applies to his vehicle's AC when flying.

All in the Reflexes
The Flyboy receives a +2 bonus to initiative while behind the stick of a plane in  Vehicle Combat.

Grease Monkey
Pilots are often called upon to make field repairs on their damaged vehicle engines or other mechanical parts. To fix a vehicle they must have the parts, take the time set by the DM, and make a successful Int check with a +1 bonus at first level, +2 at third level and +3 at fifth level.

Saving Throw
 When flying a plane a Flyboy receives a +2 bonus to all Saving Throws made to resist the effects of flax and crew damage.

XP Bonus for Dexterity
Flyboys with a Dexterity of 13 or 14 receive a 5% Experience Bonus, and those with 15 or higher get 10%.

Ace (3rd)
At 3rd level the Flyboy has a reputation as a skilled dog-fighter and Ace. At this level any vehicle weapon used by the Ace does one extra dice of damage.

Thursday, March 7, 2019

OSR In Country: Vietnam. Heavy Vehicles


A post on running Armored Vehicle combat and stats for such during the Vietnam war.
Not an expert so a few things are probably off to Veteran eye's. I did my best.

Here are the original vehicle rules these are modified from. The original rules should be used with unarmored normal vehicles such as jeeps, cars, trucks, etc.

Armored Vehicle Movement
Driving Checks
The Drive Check is simply a normal Dex roll modified by road conditions, damage, and perhaps even a Class Ability.  All penalties and bonuses are cumulative.

Most situations won't call for a check.
Taking damage, encountering and obstacle, a damaged Driver, etc will require a check to maintain control if the tank was moving.

Failure
IF the Drive Check is failed by 1-5 on the roll of d20: Slip
IF the Drive Check is failed by 6-10 on the roll of d20: Skid
IF the Drive Check is failed by 11+ on the roll of d20: Spin

Slip
The vehicle slips to the right or left (random) a number of feet equal to half of the speed it is travelling while continuing to move forward. This can bring it into a collision with another vehicle or objects.
On the Driver's initiative the next round he can roll with no penalty to the Drive check to recover. Otherwise the vehicle must be braked or it plows ahead off course.

Skid
The nose of the vehicle skews to the right or left but the vehicle continue to travels in the direction it was heading side-ways for a distance of feet equal to 1/2 of the speed it was travelling in mph. The Driver must make a Drive Check at the end of the skid or the vehicle comes to an abrupt halt. While skidding out of control it may collide with another vehicles or objects.

Spin
The vehicle spins wildly for the round and ends up facing a random (1d8) direction. If the Driver makes a successful Drive Check with a -4 penalty the vehicle can continue at normal speed if. If failed it skids to a stop after a distance in feet equal to 1/2 of the speed it was travelling in mph, now facing the new direction. If the vehicle hits an object both take damage as per normal collision rules. 

Bog Down/Hung Up
Wet environments can suck a tire or tread down fast, bogging the vehicle into an immobile state.
Mud, swampy ground, rice paddies, etc can stop a vehicle fast if care is not taken.

Trying to cross over rubble, tree piles, wide trenches, etc can have the same effect, hanging up the tank and stalling movement.

Whenever failing a Driving check by 5+ while crossing the above conditions or obstacles the Driver must immediately make another check with no penalty. If he fails this one he has become bogged down and unable to continue. He can make one more Drive check with a -8 penalty to free himself otherwise he cannot move without help from another vehicle or a major digging project.

Armored Vehicle Combat
Armor and Weapon Ratings
All armored vehicles have an armor rating of Light, Medium, or Heavy.
All armor vehicles are immune to small arms fire, machineguns, and grenades.

Heavy weaponry have the same ratings and affect how they damage vehicle armor based on these ratings.
If the weapon is the same rating as armor the vehicle will take full damage.
If the weapon is one rating lower than the armor the vehicle will take half damage.
If the weapon is two ratings lower than the armor the vehicle will take no damage.

Hard and Soft Targets
Sometimes in tank combat it's important to know how hard or soft a target is that you're shooting or ramming into. If it comes up here are guidelines:
Hard Target: Armored vehicles, metal and concrete buildings and bunkers.
Soft Target: Open trenches, unarmored vehicles, wooden buildings, etc.

Vehicle Damage
At half hit points the vehicle is at a -2 penalty to drive due to damage.
At 0 hit points the vehicle is immobile.
At -10 hit points the vehicle is either on fire as per the Fire critical result
At -20 or lover the vehicle explodes as per the Boom critical result.

Critical Hits
A roll of a natural 20 on the 1d20 attack roll is considered a critical hit and, if it does damage to an armored vehicle, causes a roll on the critical hit chart in addition to damage to the vehicle hit points. Because of the armor rules a Light vehicle weapon might hit a Heavy armor vehicle doing no damage and negating the critical hit.

Every damaging hit to the vehicle when it is at half of it's current hit points or greater is cause for a roll on the critical chart.

Find where the gunner was aiming and roll in the appropriate area (Turret, Hull, Treads) to see what happened.

APC Crits
1. Driver compartment hit. Driver takes full damage, Save for 1/2 damage. See Crew
2. Gunner MG:Destroyed.
3. Gunner hit. Gunner takes full damage, Save for 1/2.
4. Radio: Destroyed
5. Passengers: Random roll for full passengers ( 8 passengers = 1d8, etc.) hit for full damage, Save for 1/2 damage.
6. Engine Hit: The vehicle is now at half speed. If hit again the engine is destroyed. If the first hit is by five or more over the AC the engine is immediately taken out.
7. Fire: The vehicle is burning. The vehicle and all crew take 2d6 damage per round. It increases by 1d6 per round until the vehicle destroyed.
8. Boom: The vehicle explodes in  fire and shrapnel as fuel or ammo or both ignite. The crew takes full damage from the attack and an additional 3d6 fire damage each round inside the vehicle. Those within a 50' radius of the vehicle takes half damage from the attack damage, Save for 1/4 damage.

Treads/Tires
There is no chart to roll. The treads are hit and damaged. Drive rolls suffer a -4 penalty. If hit again the vehicle is immobilized. If the first hit is by five or more over the AC the vehicle is immobilized.

Tank Crits
Turret
1. Main Gun: The first hit causes a -4 penalty to all shots from damage. A second hit destroys it. If the first hit is by five or more over the AC the gun is immediately destroyed.
2. Crew: 1d3 crew (commander, gunner, loader) hit for full damage, Save for 1/2 damage. See Crew Hit Chart below.
3. Turret Jam: Stuck at current position.
4. Co-Ax (turret) MG:Destroyed.
5. Hatch torn off. If Commander standing in it he takes full damage, Save for 1/2.
6. Turret Explosion: It's gone. All crew take 5d6 damage, Save for half.

Hull
1. Radio: Destroyed
2. Bow MG: Destroyed
3. Crew: 1d4 crew (see below for random crew hit chart) hit for full damage, Save for 1/2 damage.
4. Engine Hit: The vehicle is now at half speed. If hit again the engine is destroyed. If the first hit is by five or more over the AC the engine is immediately taken out.
5. Fire: The vehicle is burning. The vehicle and all crew take 2d6 damage per round. It increases by 1d6 per round until the vehicle destroyed.
6.  Boom: The vehicle explodes in  fire and shrapnel as fuel or ammo or both ignite. The crew takes full damage from the attack and an additional 3d6 fire damage each round inside the vehicle. Those within a 50' radius of the vehicle takes half damage from the attack damage, Save for 1/4 damage.

Treads/Tires
There is no chart to roll. The treads are hit and damaged. Drive rolls suffer a -4 penalty. If hit again the vehicle is immobilized. If the first hit is by five or more over the AC the vehicle is immobilized.

Crew Hit Chart
(multiple hits on the same crew member count and diminishes hits due to other crew.)
1-2 Commander
3-4 Gunner
5-6 Loader
7-8 Driver

Aiming At an Armored Vehicle
With an extra -4 penalty on the roll the attacker, if a crit is scored, can choose a critical effect.
Turret: Main Gun, Crew, or Turret Jam
Hull: Crew or Engine Hit
Treads/TIres

Ramming and Collisions
To successfully ram a vehicle or other object a Driver must make a Drive Check with a +4 bonus. If successful the vehicle plow into its target. Tanks are good at ramming things, especially smaller vehicles.

If a vehicle is hit the rammed Driver must make a Drive Check or lose control. If the attacking Driver fails and rolls a natural 1 or 2 on the d20 the attacking Driver  must make a Drive Check of  his own or lose control.

If two vehicles are attempting to ram each other, each Driver makes a normal Drive Check with a +4 bonus. Whomever makes the highest roll has the advantage; the other Driver must make a second Drive Check or wreck his vehicle. If both miss,  nobody hit. If it's a tied roll, both take damage and both make Drive Check to see if they lose control.

Damage
Crashing or ramming vehicles take 1d6 points of damage for every ten miles per hour they are travelling. Armored vehicles multiply this damage: x2 for Light armor, x4 for Medium armor, x8 for Heavy armor.

Against unarmored vehicles a Light armored vehicle takes 1/4 damage. For collisions with other armored vehicles damage is reduced the same as if the opposing AV is a weapon of the same rating as its armor. Thus a Heavy armor tank ramming a Light armor tank would take no damage; the light tank would take full damage.
If a Vehicle rams another from behind subtract the target Vehicle's mph from the ramming Vehicle's mph. The remainder is the damage to both Vehicles and Drive Checks are required as normal. .
If a Vehicle T-bones another vehicle both take the damage from the ramming vehicle's mph. Unarmored vehicles or armored of the same rating come to a dead stop. Smaller armored vehicles are knocked aside. An armored vehicle will plow over or through a smaller unarmored vehicle.
If two Vehicles hit head-on add the amount of d6 damage from BOTH Vehicles mph and add them together for damage. Unarmored vehicles or armored of the same rating come to a dead stop. An armored vehicle will plow over or through a smaller unarmored vehicle.

When ramming buildings etc use the following guidelines adjusted for fortifications, etc.
Hard targets: concrete buildings and barricades rate as Light armor, heavy steel rates as Medium armor.
Soft Targets: Normal wood and earth rate as no armor or Light armor if thick trees, etc.

Sideswipe/Grazing//Pushing
Grazing a vehicle as a sideswipe does 2d6 damage to each vehicle and none to the Passengers. For armored vehicles follow the same damage guidelines as above. A sideswiped Driver must make a Driving check or lose control.

Pushing another Vehicle off the road or into obstacles is a Ramming Maneuver as above.

Passenger Damage
Passengers take half damage from all wrecks and collisions (except for grazing/sideswiping.)
Damage is whatever is left over from a vehicle after being reduced by armor, etc.
Passenger damage can be reduced by the following:
A seat belt reduces the damage by 25 percent.
A Saving Throw (Death) allows the Passenger to reduce the remaining damage by 50 percent.

Damage reduction is cumulative and follows the order of seat belt then Save.

If a Passenger in the Vehicle is brought below 0 hp but has more than -10hp he can make a Saving Throw (Death). IF successful the Passenger is stabilized but unconscious and in critical condition. For each hour they are without medical help they must roll another Saving Throw or die.

If they are at -10 hp or lower or the after wreck Saving Throw is failed the Passenger is dead at the wreck.

Injured Driver
A Driver at half hit points or lower have a Drive check penalty of -4.

Armored Vehicle Profiles
A quick explanation of a few vehicle game stats.

Armor Class (Ac)
Normal armor class to be hit. (Light, Medium, or Heavy armor.)

Hit Points (HP)
How many hit points the vehicle normally has.

Move
Maximum mph for the vehicle. To find combat movement in relation to characters us the following quick and easy way:  Every 1 mph the vehicle is moving multiply by 10'.
(ex: 25 mph equals 250 feet per round.)

Range
The miles the tank can travel on a full tank of fuel.

Armament
Where the weapon is mounted:
Turret: the main weapon of the vehicle, usually a cannon or launcher.
Pintle: a machine gun on a swivel mount, placed near a gunner hatch on an APC and a Commander's hatch on a tank.
Coaxial: a machine gun mounted in the turret aligned next to the cannon. It moves with the turret.
Bow: a machine gun mounted on a swivel in the front hull of the tank.

USA/ARVN
M113 Personnel Carrier
Ac: 13 (Light Armor)
Hp: 70
Move: 37 mph/ 3.6 mph amphibious
Weight: 12.1 tons
Range: 300 miles
Crew: 2
Passengers: 11 troopers
Armament:
Pintle: .50 MG: 2d12, 200', 100 belt, 2K rounds.

M-125 81mm Mortar Carrier 
Ac: 13 (Light Armor)
Hp: 70
Move: 40 mph/ 3.6 mph amphibious
Weight: 12.3 tons
Range: 300 miles
Crew: 6
Armament:
Rear: 81mm Mortar: 6d8, 20' radius, 1000' range inc, 114 rounds
Pintle: .50 MG: 2d12, 200', 100 belt, 2K rounds.

On a critical hit result of 'Passengers' the mortar and all crew are all hit as the rear of the APC is open top to accommodate the mortar.

M-577Al Carrier Command Post 
Ac: 13 (Light Armor)
Hp: 70
Move: 40 mph
Weight: 12.7 tons
Range: 300 miles
Crew: 8
Armament:
None

On a critical hit result ignore 'Gunner MG' and 'Gunner' results.

M551 Sheridan Tank
Ac: 14 (Light Armor)
Hp: 120
Move: 40 mph/ 3.6 mph amphibious
Weight: 17 tons
Range: 470 miles
Crew: 4
Armament:
Turret: 152mm Heavy Cannon: 5d6x6 HE/HEAT,30'/15' radius, 600' range inc., 20 rounds (AP, HE, HEAT)
Pintle: .50 MG: 2d12, 200', 100 belt, 1K rounds
Bow: 7.62 MG:  2d8, 200', 100 belt, 3k rounds

Caseless Ammo: When hit with a turret or hull critical there is a 70% that the rocket or mine sets off the ammo outright destroying the tank and killing everyone inside in an inferno.

M41 A3 Walker Bulldog Tank
Ac: 14 (Light Armor)
Hp: 170
Move: 46 mph
Weight: 23.5 tons
Range: 100 miles
Crew: 4
Armament:
Turret: 76 mm Medium Cannon, 5d6x2 HE, 20' radius, 600' range inc., 57 rounds (AP, HE, HEAT, WP)
Pintle: .50 MG: 2d12, 200', 100 belt, 600 rounds
Coaxial: .30 MG: 2d6, 200',100 belt, 5.225K rounds

M48 A3 Patton II
Ac: 15 (Medium Armor)
Hp: 200
Move: 40 mph
Weight: 52 tons
Range: 287 miles
Crew: 4
Armament:
Turret: 90 mm Medium Cannon: 5d6x3 HE/HEAT, 25'/15' radius, 600' range inc., 64 rounds (AP, HE, HEAT, WP, Beehive
Pintle: .50 MG: 2d12, 200', 100 belt, 3K rounds
Coaxial: .7.62mm:  2d8, 200', 100 belt, 10K rounds

M60 Main Battle Tank
Ac: 15 (Heavy Armor)
Hp: 240
Move: 30 mph
Weight: 60 tons
Range: 310 miles
Crew: 4
Armament:
Turret: 105mm Heavy Cannon, 5d6x5 HE/HEAT, 25'/15' radius, 600' range inc.,
Pintle: .50 MG: 2d12, 200', 100 belt, 3K rounds
Coaxial: .7.62mm:  2d8, 200', 100 belt, 10K rounds

NVA
Soviet PT-76  
Ac: 14 (Light Armor)
Hp: 120
Move: 27 mph / 6 mph amphibious
Weight: 14 tons
Range: 155 miles
Crew: 3
Armament:
Turret: 76mm Medium Cannon: 5d6x2 HE, 20' radius 600' range inc., 40 rounds (AP, HE)
Coaxial: .7.62mm:  2d8, 200', 100 belt, 1K rounds

Soviet T-55  
Ac: 14 (Medium Armor)
Hp: 170
Move: 30 mph
Weight: 36 tons
Range: 310 miles
Crew: 4
Armament:
Turret: 100mm Medium Cannon: 5d6x4 HE/HEAT, 25'/15' radius, 600' range inc., 43 rounds (AP, HE, HEAT)
Coaxial: .7.62mm:  2d8, 200', 100 belt, 1K rounds

Tank Cannon/Guns  
Here are some cannon stats for tanks.
The base damage is based on the High Explosive (HE) shell. There are three increments to the radius as in my Artillery rules here. This damage is used and modified for other shells.

Shell Types
High Explosive (HE, tipped with an explosive warhead.)
Standard damage round. Most effective against soft targets and infantry.

High Explosive Anti-Tank (HEAT, a shaped HE warhead designed to penetrate tank armor.)
An extra x1  to damage vs vehicle. Explosion arcs out in a 180' arc from point impact on vehicle or hard target. Automatic half damage to soft targets (personnel, animals, etc.) and may Save for another half damage.

White Phosphorus (WP, incendiary shell.)
Explodes in the normal radius for the shell. It burns for 2d6 damage for six rounds.
Damage is not reduced by radius increment but those hit do receive a bonus to their Saving throw for half damage.  The second increment gives a +2 bonus to the Save and the third increment gives a +4 bonus to the Save.

Canister//Beehive round.
Similar to the artillery version it is a shell packed with thousands of flechettes (small darts like nails). It is a vicious area effect weapon used against personnel especially those hidden in dense foliage. this shell does 3d6 damage to all targets in a cone attack starting 2' wide at the firing weapon and extending in a cone 1200' in length and a 300' width at it's end.
Everyone and everything not undercover can make a Saving Throw for half damage.
Those under soft cover automatically take half damage and can make a Save to halve it again with a bonus to the Save equal to cover bonus.
Those under hard cover or in an armored vehicle take no damage if totally covered. If partially exposed they will take damage and Save as if under soft cover above.

Because if the rarity of tank to tank combat the most popular shells were HE and canister. WP was useful but dangerous if hit in a tank. AP and HEAT were the least used.

Armor Piercing (AP, non-explosive solid rounds.) Rarely use in Vietnam.
An extra x1  to damage vs vehicle.
(Ex: a 75mm AP round would do 5d6x3, not x2.)


Light            Dmg (HE)  Radius Notes Range Inc 600'
20mm 3d6             5' Auto 3/rnd
40mm 5d6            5'

Medium       Dmg (HE)  Radius Notes Range Inc 600'
75mm 5d6x2 20'
88mm         5d6x3 20'
90mm         5d6x3 25'
95mm         5d6x4 25' HEAT Radius- 15'

Heavy          Dmg (HE)  Radius Notes Range Inc 600'
105mm       5d6x5 25' HEAT Radius- 15'
150mm       5d6x6 30' HEAT Radius- 15'

NVA/VC Anti-Tank Weapons
The communists used a popular Chinese 75mm Recoilless Rifle. It was light and had a good punch.
Functions the same as the 75mm tank cannon.
Armed with HE and HEAT rounds.

Smoke/Smoke Mortars
Smoke from explosions, fires, etc can play havoc in vehicle combat. An obscured vehicle is more difficult to hit, just as an obscured character is, and can hide movements. An obscured vehicle receives an AC bonus or +2 to +6, but it also takes a penalty equal to this amount if attacking from within the smoke. If an obscured vehicle fires from within the smoke it gives its position away and its AC bonus is halved. .

Smoke mortars on vehicles create a wall of smoke that will obscure it and its movement for 1d6+2 rounds. Smoke/WP shells could also be fired towards an enemy to cause confusion.

Cover
Vehicles can take advantage of cover such as burned out buildings, trees, and shallow depressions in the ground (going 'hull down.') Cover works the same as for a character giving a bonus based on how much of the vehicle is hidden. Camouflage netting may aid in the cover bonus.

For hard cover such as a concrete/brick walls or hiding behind a rocky hillside or burnt out tank:
+2 AC light, +4 for medium, and +6 for heavy cover.

For soft cover such as trees, an earthen hillside, etc. halve the cover bonus.



Wednesday, March 6, 2019

OSR In Country: Vietnam. Artillery


Rules suggestions for Artillery and big explosions.

Blast Radius
Artillery, tank cannon, and other big guns have a large blast radius. There are three extending blast radius'  measured in feet. The further from the center of the explosion the less damage personnel and vehicles will take.

There are three incremental radii to such explosions, each measured in feet.
  • The first radius extends a set amount of feet. (For example let's say 20')
  • Multiply x2 feet for the second. (21' to 40')
  • Multiply x3 for the third increment. (41' to 60')
Damage done by Radius:
First: Full damage dice.  Personnel (your men and the enemy combatants) Save for 1/2 damage.
Second: half damage dice (round up.) Personnel Save for 1/2 damage.
Third:  half again damage dice (round up.)  Personnel Save for 0 damage

Cover bonus applies to saving throw.
Full cover may completely protect a character if the DM decides it is strong enough (use the light, medium, heavy armor/weapon rating for Vehicles below for guidelines.)

Basic Artillery Rules
There are several options available. A few are:
WWII Operation White Box by James Spahn

Recon from Palladium

Weird War II: Blood on the Rhine and other games from Pinnacle

All work very well and all pretty much work the same in each system:
⦁ You use your own mortar or you call in to see if Heavy Artillery is available.
⦁ Some roll is made to see if it is available/ what is available/ how much is available.
⦁ Rolls are made to see how long before the barrage will begin.
⦁ Rolls are made to see if/how close artillery hit.
⦁ Rules to do various things such as re-adjusting hits on the target, firing for effect, etc.

Heavy Arty Availability
Some missions will not have Heavy Artillery available due to it being diverted for other operations, stealth concerns, etc. It will vary.

When available on missions Heavy Artillery should be used sparingly. Over calling will result in it not being available as some REMF decides you do not need it. As a DM more than once a day for non-dedicated non-search-and-destroy target missions will be about it. Dedicated fire support will most likely be readily available as specific targets are located, not to get the PC's out of every fire fight.

If the team's mission has been given dedicated fire support it is vastly more likely it will be available. If not the chances of having support are greatly reduced. It's a crap shoot. At one point in time there were over 200 batteries of artillery were scattered over the country and often fire could overlap.

When in the field and the PC's think they need it they must roll to see if fire support is available
Roll a 1d6. A roll of 5 or 6 indicates it is available.
Dedicated: +3
Non-Dedicated: +0

What's available?
Roll a 1d6:
1 Heavy Mortar
2-3 Heavy Artillery
4-5 Gunship
6 Air Strike

How Long?
Average response time is 60 to 90 seconds.
Find how many points under his Int/Radio check the FO succeeded on his roll.
Subtract this from 15 to find how many rounds it takes for the first shell to impact (minimum 6 rounds.)

How to Hit? (Forward Observer)
Heavy Mortar and Artillery
To target the enemy and to make adjustments to the roll requires an Intelligence/Radio check. Those unskilled have a -4 penalty to the check. After the response time has elapsed a single spotting round will impact the ground on the FO who called it in's initiative. This will be the initiative for any following shells.

If the FO roll is passed the strike is on target. If it is failed the shell deviates from its intended target and lands in a random direction (use the 1d8 or 1d12 clock method) landing 2d10 x50 feet off target.

Re-Adjusting Fire
The next round the FO can call in another spotting round and try to hit the intended target with a +4 bonus to the FO roll (and a +8 if he takes another round after this but +8 is the maximum.)  If successful the re-adjusted fire hits and he can call in a Fire or Effect barrage. If failed the shell deviates but lands only 2d10x20 feet off target. This will be the deviation the next round, etc.

The FO can 'walk' the rounds over to a new target this way.

Fire for Effect (FfE)
When the target has been hit the FO can call for Fire for Effect. The battery fires with all of its guns and loaders.
Multiple shells impact on each combat round equal to it's rate of fire (RoF.)
The duration shows how many rounds the barrage lasts before the battery is exhausted, redirected, etc. A new strike, if called immediately after, gains a +8 to the FO's roll.
The shells are not as accurate as a spotter round . Roll the deviation for each shell that round.

USA/ARVN
Artillery               Dmg Inc RoF   Duration FfE Deviation
Hvy 4.2"  Mortar 10d6 35' 1d3        1d6+1       2d12x5 feet
105mm Howitzer 5d6x4 35' 1d3+1   1d6+1 2d12x5 feet
155mm Howitzer 5d6x5 50' 1d2+1   1d6 2d20x5 feet
203mm Howitzer   5d6x6 70' 1d2+1 1d4 2d20x5 feet

NVA/VC
130mm         5d6x5 50' 1d2+1   1d6 2d20x5 feet  
Required an 8 man crew.

Canister//Beehive round.
A  105mm shell packed with thousands of flechettes (small darts like nails). It is a vicious area effect weapon used against personnel especially those hidden in dense foliage. The shell does 4d6 damage to all targets in a cone attack starting 2' wide at the firing weapon and extending in a cone 1200' in length and a 300' width at it's end.
Everyone and everything not undercover can make a Saving Throw for half damage.
Those under soft cover automatically take half damage and can make a Save to halve it again with a bonus to the Save equal to cover bonus.
Those under hard cover or in an armored vehicle take no damage if totally covered. If partially exposed they will take damage and Save as if under soft cover above.

Gunship
Gunships will come in and chew up a position. They will stick around until they start taking serious ground fire (especially RPG's) or run out of ammo. Each round they will unload with all available weapons on the ship.

Pilot(s):  Attack +2, +3 to Dex/Piloting
Gunners: Attack +3

Hog (Huey)
Two M-60's, door gunners.
Target up to six hostiles per round in a line ten feet wide and fifty feet long.
+4 to hit.
Damage: 4d8 per hit.

40mm automatic grenade launcher, nose, pilot.
Attacking Ac 10 (Area attack)
Blasts an area up to thirty feet wide and 100 feet long per round.
Damage is 6d6. Soft targets save for half.

2.75 in (70 mm) rockets -  M200 19-tube rocket launchers,  2 pods, pilot.
Attacking Ac 10 (Area attack)
Blasts an area 40' wide by 40' per pair of rockets fired. Can fire up to up to 36 pair per round.
Damage: 6d6, Light Weapon, Soft targets save for half.

Snake (Huey Cobra)
7.62 mm multi-barrel Miniguns, right front turret, pilots.
Target up to 12 hostiles per round in a line ten feet wide and 100 feet long.
 ⦁ +4 to hit.
Damage: 4d8x2 per hit.

40mm automatic grenade launcher, left front turret, pilots.
Attacking Ac 10 (Area attack)
Blasts an area up to thirty feet wide and 100 feet long per round.
Damage is 6d6. Soft targets save for half.

2.75 in (70 mm) rockets -  19-tube rocket launchers,  1 or 2 pods on each wing, pilots.
Attacking Ac 10 (Area attack)
Blasts an area 40' wide by 40' per pair of rockets fired. Can fire up to up to 36 pair per round.
Damage: 6d6, Light Weapon, Soft targets save for half.

Airstrike
Napalm, bombs, or possibly AC-47 Spooky (Puff the Magic Dragon.)
Whole sections of the jungle go away. Hills get flattened. Bunkers crack like eggs. Fire and the wrath of Uncle Sugar. The scale of this kind of devastation is almost unimaginable from the ground.

Currently beyond the mechanical scope of what I want to do. Maybe later.
For now the GM will decide the outcome of an airstrike.
If it gets too close to the PC's and allies may take a few dice of damage at the GM discretion. Good luck.

Mortars
The attack roll uses the gunner or FO's base hit bonus + Int modifier vs a stationary target Ac of 10 + range modifiers. A moving target is always Ac 20 plus range modifiers and only one shot per round can be taken.

If it is failed the shell deviates from its intended target and lands in a random direction (use the 1d8 or 1d12 clock method) landing 2d10 x25 feet off target.

Once on target no attack roll is needed for a stationary target but deviation is rolled for each shell. IF the target moves to a new location the mortar must re re-adjusted.

USA/ARVN
Mortar Dmg    Inc' RoF Range'        Deviation 
Light
M-2  60mm 5d6      15'      2      500' 1d6x5 feet
⦁ 60mm WP 2d6 (Burns for six rounds)  

Medium
M-29  81mm 8d6     25'        2   1000' 1d10x5 feet
⦁ 81mm WP 2d6 (Burns for six rounds)  
⦁ 81mm Parachute Flare (up 1800 feet and light up a 3000 ft area for 1 minute)

NVA/VC 
The communist forces used a 60mm and an 82mm, both equivalent to our 60 and 81mm.

Mortars and their shells are heavy. Most mortars break down into three pieces: tube, bipod, baseplate. The baseplate is the heaviest, half the weight of the mortar. The M-19 60mm is split among a three man crew (squad leader, a gunner, and a loader.) The M-29 81mm normally crewed by a 5 man team (squad leader, a gunner, an assistant gunner and two loaders.)

Artillery vs Vehicles
Vehicles caught in the radius of a mortar take damage normally depending on  their armor rating vs the mortar rating
A direct hit from a 150+  mm HE shell from above straight up destroys the vehicle and everyone takes full damage. Everyone in the tank then is on fire for 2d6 damage per round until they escape the vehicle. Everyone within the three radii of the shell take normal damage with Saving throws.