Guided Weapon Attacks

WW2 saw the beginning of air-launched guided stand-off weapons, that is, weapons that could be dropped off from some distance away from the target and then would be guided the rest of the way target, saving the delivery aircraft from having to travel all the way into the enemy's air defenses. This concept is in used today as cruise missiles.

This was of particular value to the Luftwaffe. Allied air defenses grew increasingly lethal due to the volume of AAA and fighters available, and if the Luftwaffe was to retain any ability to strike back at all, some means of preserving their striking arm was required. To counter this growth trend, Germany sought a technological advantage with goals that resonate today:

Preserve its striking arms by keeping them out of defensive range (like today's cruise missiles)
Provide a means of upgrading attack capability without developing a new aircraft.

These initial weapons were crude by today's standards, but were quite sophisticated for WW2.

The first remote-guided weapons were anti-shipping weapons fielded by Germany. In August, 1943, the Luftwaffe introduced into combat both the Hs293 rocket and the FX1400 Glide bomb. Both were winged bombs, one rocket assisted, designed to be launched away from the target and directed by the bombadier of the parent aircraft over a radio link. They also produced the Hs294 rocket to carry a torpedo to enemy shipping and air-launched the V-1 "cruise missile" when their launch sites in Belgium were seized or destroyed. The Germans were developing additional weaponry for ground and air attack that did not quite make it to the flight line before the war ended. In any event, these weapons were not present in enough numbers to have a major effect on the war.

Nor were the Germans alone in developing weaponry along these lines: the Japanese were developing similar weapons, and the United States used the ASM-2B Bat guided glide bomb as well as the GB and VB series of guided weapons..

These rules are devised for the use of these early guided weapons.

Definitions

Guidance

These weapons needed to devlop two technologies to provide guidance:

A means of steering the weapon during its attack
A means of transmitting instructions to those steering controls.

The actuators to control flight was not that difficult. The question became how would a remote guider know where to fly. There were three types of Guidance:

Type	Description	Code
Piloted	Yes, this means Pilot on board, usually for a one-way trip. This is for aircraft that are dropped from a parent.	P
Remote Guided	The weapon is guided remotely by a human operator over a radio (/R) or wire (/W) link. Radio links were vulnerable to jamming. Wire links were vulnerable to breaking.	RG/R RG/W
Self-Guided	The weapon is guided by a device aboard the weapon. It requires no additional input once launched.	S

Dud Rate

As these were the cutting edge of the technology of their day, these weapons suffered from a certain dud rate due to a failure of the guidance communication system or the motor or the explosive fuse. After launching a weapon, roll 1 D10. If the roll is equal to or less than the weapon's dud number, the weapon falls ballistically or fails to explode.

Modifications
Aircraft damaged: +2

Flight Profile

The weapon's flight profile describes movement or launch limitations that the weapon or its guiding aircraft are required to follow.

Tactical/Operational Scale Attacks

If there is no intercept, and you do not wish to perform a combat scale weapons realease, check against the weapon's dud rate, then go to the target roll.

The target must be sighted (or in radar contact) during the Op-scale turn (or on a previous op-scale turn and the sighting maintained) before the attack is made. Exception: Bv246 can be fired blind with a penalty.

Treat all of these weapons as "jet powered" for Tactical or Operational scale movement, but note restrictions for each weapon. Guided weapons do not require aiming (nor do they gain any addition for turns spent aiming)

Weapon

On Successful launch...

FZG-76 V-1

Becomes a separate flight on the Ops track. Eligible to receive fire in AA phase where appropriate. If not shot down or caused to crash, it strikes its "strategic" target on a 3-. Otherwise, it scatters and strikes a nearby target.

**Modifiers**:
AAA Modifier		-2 (flew very straight; no jinking)

Fi103R

Piloted version of the V-1. Treat as piloted aircraft. Pilot points the aircraft at target, then attempts to bail out. It strikes its target on a 3-. Otherwise, it scatters and strikes a nearby target.

**Modifiers**:
Vet, Ace, or GF pilot:		-1

MXY7 Okha

Becomes a separate flight. Must attack a spotted target in the current operation-scale box or hex. Undergoes AA phase if unopposed by aircraft. If not shot down, it attacks a target. Hit on a 3-.

**Modifiers**:
Vet, Ace, or GF pilot:		-1

FX1400
Hs293
Hs294
Igo-2-B

Must attack target in the Ops box or hex. Hits on a 4-.

**Modifiers**:
Vet bomber crew:		-1
Green bomber crew		+1
Igo-2-B		+1 (less mature technology)

In tactical mode, guiding aircraft must avoid diving for 3 tactical turns or attack aborts.

Bv246B Hagelkorn

Roll to detect an active radar target in the current or an adjacent Ops Box. Use Dud Rate as detection roll. Hits on a 3-.

**Modifiers**:
Target in adjacent Ops box:		+2 (to Dud Rate roll)
Fired blind (not at a known target):		+2 (to attack roll)

ASM-2B Bat

Must attack fixed target in the Ops box or hex. Target must have already been spotted by parent aircraft. Hits on a 4-.

Combat-Scale Attacks

Combat-Scale Launch

These weapons can be used during Combat scale attacks. Deploy these weapons as follows:

Weapon is dropped at the end of a turn. The parent aircraft must fly straight the turn it drops the weapon. With this declaration, place a counter for the weapon.
At the beginning of the next turn, check against the weapon's dud rate. If the weapon fails, remove it form play.
The weapon begins the next turn with the parent aircraft's speed, altitude, and attitude. The weapon (and guiding aircraft if applicable) must adhere to any limits described in its flight profile, which varies by weapon.
Only 1 guided weapon can be dropped each combat turn.

As X class aircraft, self- or remotely guided weapons always move first. Piloted weapons move as F class and figure their initiative normally.

AAM Combat Rules

Early AAMs were particularly clumsy weapons. Their use is controlled as follows:

AAMs can only be used to attack bombers in fixed formations, or individual Heavy bombers.
AAMs move directly after H class.
The AAMs maneuver normally per their ADCs.
When an AAM moves into the same hex/altitude as a target, it can attack per its ADC.
If the AAM does not attack and still has movement points left, it can continue to move toward another bomber.

Movement of Guided Weapons

Since the weapons are tactically flown (like aircraft), ignore release point requirements, release point modifiers, and additional aiming turn modifiers. You fly your weapon to the target and then figure out the attack. However, plan your releases carefully as the weapons are not terribly maneuverable, and some of the restrictions due to guidance limitations make such plans important.

Guided weapons that lose contact with their parent, either because the wire breaks or because the weapon's control frequency is jammed become ballistic, continuing on the same trajectory. The weapon loses the -3 Guided Weapon bonus. Unless the weapon is about to strike its target, rmeove it from play.

A parent aircraft can only guide one remote-guided weapon at a time. The first weapon must either strike its target or lose contact before a second remote-guided weapon can be fired.

If the aircraft pilot is guiding the weapon, apply a -2 modifier to his initiative for each turn that begins with the pilot guiding the weapon.

Movement of Self-Guided Weapons

Self-guided weapons move straight toward their target with little maneuvering. If the target is within a front 15° cone (both horizontally and vertically), the weapon will fly straight. As the target drifts out of the front cone,

Roll a D10.
If more than the weapon's dud rate, the weapon executes an EZ turn or transition, or a slide or a skid in the direction of the target (to be more on target than off target). The weapon does not turn more than 30° or change more than 1 attitude per turn.
If the roll is equal to or less than the dud rate, it does not turn or change attitude, but may attempt to do so next turn.

If the target drifts out of the front 60° cone for the weapon, it goes ballistic and flies straight. If it is guiding along an emission and continues to receive that emission or another of the same type, it will continue to guide on the new emission.

Gliding Weapon Notes

Glide bombs, missile weapons after their fuel runs out (and gliders in general) are affected by the following rule changes to fit the characteristic of glider flight:

If not in stalled flight, and the weapon does not accellerate that turn (either by engine accelleration or by diving), it incurs 3 decel points in addition to any points earned by turns, maneuvers, or climbing.

Attack Modifications

Apply the following modifications:

Guided Weapon:	-3	Weapon damaged	+2
Veteran Bdr/Pilot	-1	Target is ship at sea	-2
Green Bdr/Pilot	+1	Target is prominent against surrounding terrain*	-1
Recruit Bdr/Pilot	+2	Target is prominent against surrounding terrain*
Bdr/Pilot wounded:	+2

* For example, a ship at sea against the horizon or a bridge rising over a river plain.

Weapons

This table provides a rough description of several early guided weapons. Some are described in more detail in a set of ADCs (available on Uncle Ted's).

Weapon	Nation	Description	Dud Rate
Hs293	Germany	Based around the warhead from a SC250 (250 kg) bomb, the Hs293 was designed for use against lightly armored vessels. Radio-controlled by the bombadier of the parent aircraft. Other guidance systems tried included wire-guided, homing radar, and TV form the nose of the missile. Guidance: RG/R (bombadier watching flare) Flight profile: Dives 300 ft the first turn, then continues under guidance from parent aircraft. Parent aircraft climbs 300 ft the first turn. Must keep missile in front arc so bombadier can continue to guide.	3
Hs294	Germany	Similar to the Hs294, but with a larger wing-span and carrying a torpedo. Good glide-ratio. It was designed to damage lightly-armored vessels beneath the water-line. Radio-controlled by the bombadier of the parent aircraft. Guidance: RG/R (bombadier watching flare) Flight profile: Dives 300 ft the first turn, then continues under guidance from parent aircraft. Parent aircraft climbs 300 ft the first turn. Must keep missile in front arc so bombadier can continue to guide.	3
Hs298	Germany	Early Air to Air missile. Developed in parallel with X-4 until Dec. 1944, when X-4 selected for production Guidance: RG/W (with terminal acoustic fuse) Flight profile: Turn of launch, the missile moves the speed of the parent aircraft + 1.5 FP in hexes and then moves normally (including accelleration). Continues for a maximum of 27 hexes, then explodes anyway. See the ADC for attack details. The guiding aircraft must make only EZ turns and must keep the missile in his front arc. If a sharper turn is made or the missile gets out of arc, the guiding wire breaks and the missile flies straight and level on its last heading.	4
FX1400 Fritz	Germany	Glide bomb based around an SD250 armor-piercing bomb. Designed to attack heavily armored warships. Two FX1400 hits sank the modern Italian battleship Roma in September 1943. Radio-controlled by the bombadier of the parent aircraft. Guidance: RG/R (bombadier watching flare) Flight profile: Dives 300 ft the first turn, then continues under guidance from parent aircraft. Parent aircraft climbs 300 ft the first turn. Must keep missile in front arc so bombadier can continue to guide.	3
Bv246 Hagelkorn	Germany	Glide bomb developed around 1943 with fantastic glide ratio, but no decent guidance system. Revived in early 1945 and given early radar seeking self-guidance system. The aircraft must detect an active radar before firing. Guidance: S (Radar-seeker) Flight profile: Enters an immediate shallow dive, heading toward the detected radar. Drops .1 alt, 1 VFP per turn until target is more than 15° vertical; then moves to steeper dive. Uses slides and skids for later movement only	5
Ruhrstahl X-4 (early AAM)	Germany	Early Air to Air missile. Had entered production when the factory with the first 250 motors was destroyed in Jan. 1945. Guidance: RG/W (with terminal acoustic fuse) Pudel seeker: S (accoustic seeker) Dud=6 Flight profile: Turn of launch, the missile moves 11 hexes and 14 hexes on subsequent turns. After moving 15 hexes, it is amred and can go off on detecting a target. Continues for a total of 4 turns, then explodes anyway. See the ADC for attack details. While guiding, the guiding aircraft must make only EZ turns, and must keep the missile in his front arc. If a sharper turn is made or the missile gets out of arc, the wire breaks and the missile flies straight and level on its last heading.	2
FZG-76 aka V-1	Germany	The V-1 Buzz Bomb (named for the sound of its pulse-jet) was a guided by a gyroscope on a preset course. It was quite accurate, striking within a few hundred yeards of its (intended) target from 50-100 miles away. Originally fired from the ground from launch sites in France and Belgium, V-1s were adapted to be fired from He-111H-22s and launched form over the North Sea at Britain in the Fall and Winter of 1944. Guidance: S (gyroscope autopilot) Flight profile: Dives 300 ft the first turn, then slowly drops to its flight altitude (200-1500 ft) in a shallow dive (1 VFP, .1 alt per turn). From then on it flies straight at its target along a preset course. It can self correct to maintain course (gyroscopic guidance system). The parent aircraft climbs 300 ft the first turn, then drops behind V-1, matching course and altitude to throw off the (radar-guided) interceptors before returning to base.	1
Fi103R	Germany	Manned version of the V-1. Not exactly a suicide rocket; the pilot was supposed to bail out before sending the missile to its final target - but getting out was not a good proposition. Not used in combat, although a unit was trained to fly them. Guidance: Piloted Flight profile: Dives 300 ft the first turn, then acts as piloted aircraft. Continues on course after pilot ejects.	1
MXY7 Okha	Japan	Piloted glide bomb with a large (600 kg) warhead. The idea was to release the pilot to select the largest vessel in the area (preferably an aircraft parent) and attack it. Guidance: Piloted Flight profile: Drops 2-300 ft the first turn to clear its parent aircraft the first turn. Then acts as a piloted aircraft within its abilities. Use Kamikaze rules for pilot determination and targeting.	1
Igo-2-B	Japan	Similar in concept to the German Hs293, Igo-2-B was in flight test at the end of the Pacific war. Radio-controlled by the bombadier of the parent aircraft. Guidance: RG/R Flight profile: Drops 2-300 ft the first turn to clear its parent aircraft the first turn. Then acts as a piloted aircraft within its abilities.	6
ASM-2B Bat	USA	Glide bomb used by USN in the Pacific launched from PB4Y-2B (USN version of B-24). Guided by its own radar to a target. Worked best against large, fixed targets like bridges and beached freighters. Guidance: S (own radar) Flight profile: Target must be detected by radar 2 turns before launch. Target must be in fornt arc at launch. Glides, seeking to keep target in forward 15° cone. If the weapon starts a turn with the target beyond the cone, it changes direction toward the target. Does not turn more than 30° or change more than 1 attitude per turn. If there are multiple targets in the front 15° cone, the Bat targets the closest one. If there are two equidistant, select the target at random.	2
VB-1 Azon	USA	1000-lb bomb rigged with AZimuth ONly guidance system. Azon was first deployed in Feb-44 against the Danube river locks in Tyrolia, then against the Seine River bridges in May-44, and in Burma in Jul-44 against a railroad bridge in Burma that had been missed by thousands of bombs. Azon was 10-20 times as accurate at normal weapons. Guidance: RG/R (bombadier watching flare) Flight profile: The bombadier could control up to five bombs at a time. The bomb run is executed normally, but the bomber must fly straight (on a continuation of the bomb run) until the bombs strike. If the bomber is forced off its path, lose guidance and treat the bombs as unguided. When the bombs hit, figure all scattering normally, then move bombs one hex left or right toward target hex without passing across the bomber's path.	2

Historical Commentary

Stand-off, guided weapons was a new idea developed in the crucible of combat as a combat multiplier. In the Luftwaffe's case, the purpose was to preserve its bomber fleet the development of which had not kept up with technology and could not in any event stand up to the increasing hordes of Allied fighters. To strike from a ways off, and to be able to strike more efficiently (1 bomb, 1 target) was the goal. The Japanese had the same needs but fewer development and technologic resources to throw at the problem.

To me, this not not very different from the "quality vs. quantity" development and production logic that the US and other Western nations followed since the end of WW2 during the Cold War for the defense of western Europe. Was this a viable strategy? History shows that the weapons were not developed in time and that by and large, the promise of advanced weapons did not pan out for the Wermacht (particularly the Luftwaffe), the effect of new weapons not making up for the effort to develop them.

(Among the problems facing the Luftwaffe was that their electronics development was behind that of the allies. The allies could develop counter measures to German electronics more easily than the Germans could develop the next advance. Having a powerful research and industrial region out of the combat zone (that is, the United States) helped a lot.)

The United States had the resources to through at the problem - but less need, and pursued its research with less urgency. The ASM-2b was the heir to three research projects for weapons that were ultimately determined not to be needed before a self-guided glide bomb was developed.

To me, among the more interesting points about these weapons is

that they worked as well as they did considering the state of 1940s electronics.
that they used concepts later ignored by the victorious allies for a decade or more, and then were picked up again from scratch as new ideas.

NJ Hickman wrote about dropped weapons. I strongly disagree with the ADCs he created in that they do not match what I have read about the weapons' flight capabilities nor match the flight model I use to build ADCs. But his history of the German use of guided weapons (at the end of the piece) is spot on and well worth reading.

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