Laser guided bombs - who paints the target?

Factual Questions
1

After hearing about how a good portion of the bombs we’re dropping on the Taliban are laser guided, I began to wonder how that little red dot got there in the first place. My first thought would be the aircraft delivering the ordinance, but keeping a laser trained on a target thousands of feet away while manuvering and being buffetted by winds sounds a little far fetched. The other posibility would be something akin to what I saw in ‘Clear and Present Danger’ (I think that’s the movie) and ‘In the Army Now’ where a hidden ground troop shines a light on a target to be taken out by a plane 5,000 feet up.

Granted I’m not going to take Pauly Shore at face value, but Clancy is a bit more reliable. So what’s the SD on this?

2

The planes paint the target. I think the pilot initially orients the laser to point at the target and then the computerised weapons systems take over and keep the dot on the target as the plane flies. I’m sure using different devices (gyroscopes, GPS, etc) the laser is kept quite steady.

3

Either the attacking aircraft, another aircraft, or special forces on the ground can paint a target for a laser-guided bomb or missile. It’s quite common for the attacking aircraft to do the job itself.

4

Mirage, you came to the right place with this question.

Quite honestly, there’s a number of different ways the target is painted. The most commonly used would be, in no specific order:

[ul]
[li]Self-Designation[/li][li]Forward Observer[/li][li]Alternate Designation[/li][/ul]

Self designation, which I believe to be the most commonly used method of delivery, requires a rather advanced avionics package. A good example of this sort of system, and in fact, the system that I worked with in operations Deny Flight, Deliberate Force, (ad nauseum) was the LANTIRN system (Low Altitude Navigation and Targeting InfraRed for Night), for my purposes used on F-16 C&D models, as well as the F-15 E. LANTIRN, in essence, replaced the Pave Tack system, used on F-4 and F-111 jets.

With the LANTIRN system, the pod has the ability to auto-track the target, as well as a manual steer by the weapons operator. The laser splash, tracked by the bomb, isn’t a small dot by any means. Also, the laser is not continuously fired, rather used at specific timesto point the bomb in the proper direction. Were the operator to continuously fire, the trajectory would be off, and the bomb will fall short.

Aircraft such as the A-10 use a smaller system, without many of the advanced avionics features. Read here about Pave Penny, a system which is beginning, in my opinion, to become obsolete.

Pave Penny systems would necessarily rely upon a forward observer or alternate designation (e.g. a dude on the ground wth a laser, or another jet with lasing capability) to illuminate the target.

And 5000 feet up? peanuts :slight_smile:

5

Thanks for the info Hecubus (I never did like the way that Simon treated you). Once again I’ve underestimated that feats that modern technology has managed to accomplish. Why would the constant beam throw the trajectory off? Does the aircraft keep track of the bomb and flash the laser to correct it in the way that it sees fit?

6

Well, one of the factors is that the bombs are not necessarily just dropped, but rather “lofted”. Think about it like pitching a softball. (At least, this is the way we did it back in flight test at Edwards.)

When you release the softball, it arcs up, and travels down to reach the catcher’s glove. if there were a way to, at the apex of the arc, steer it for just a moment to give it a better track to the target, you’d throw a gazillion strikes.

BUT…were you to start steering too soon, and for too long, you might cut the arc too short. Since gravity is a constant, and the pitch is relying on reaching a certain altitude and range before descending…you’re slicing off too much of the distance, and hitting early.

It’s tough for me to explain :slight_smile:

7

It’s actually not all that complicated. It’s fairly simple trigonometry to keep a target stabilized on a point when you start with the range (via laser return) and angle to that point and know how the aircraft itself is moving/maneuvering. I’m not sure if LANTIRN does, but some systems also use image recognition to keep on target in the same way that some guided missiles do…this can be more effective in some ways, and is the only way to deal with moving targets other than manually, but is a LOT more complicated than the dead-reckoning method.

The only real drawback to self-designation is that it puts a higher workload on the pilot, which can be a concern in the F-16 where the pilot is doing everything. As I understand it, having a wingmate designate while another aircraft drops is fairly common in single-seaters.

Not a problem at all for the 2-seat F-15 though.

8

Also note that while ‘loft’ is on method of delivery, there are others, including a high-altitude drop that gives GBUs a reach of miles (more than 10 nautical miles in the case of the GBU-24). In this case it may be unreasonable to have the launching aircraft designate, so the target will be illuminated by another aircraft or by ground forces. One designator aircraft could theoretically orbit an area with a target list, desgnating target after target while other aircraft shuttle GBUs into the area, drop, and depart, never knowing where their bomb went.

From FAS, a description of ‘loft’, as it applies to GBUs:

9

Some of the planes that deliver laser guided bombs are two-seaters. The pilot flies the plane so the Weapons Systems Officer (WSO – pronounced whizzo) can concentrate on keeping the target painted.

10

Another option is using JSTAR aircraft to paint it. Ground designation is used more with TOW missles and laser-guided mortars.

11

Why, Ding Chavez and John Clark, of course!

::runs away::

12

I think the best case situation (cause I’m cool like that) is a Maverick handoff. That’s some good stuff right there.

Lantirn didn’t employ a true image recognition algorithm when i was working it, but did have an area track feature, locking contrast. However, when flying through THICK clouds and smoke, you CAN lose that tracking capability, in which a rate track function comes into effect, utilizing the computational features of the control system.

Also, Tranquilis has mentioned solid points. Especially in the FAS website, when you review bomb run footage, you’ll notice that the lasing symbology isn’t necessarily flashing from the targeting pod the video is captured from. In that instance, it’s likely a team designation or forward observer.

Still, my fave part of the bomb video is watching the TTI indicator tick it down :slight_smile:

13

this may be a bit simplistic, but couldn’t you fool a laser guided bomb, but simply bathing the entire compound in red light (of whatever wavelength the laser is). I know that the bomb would probably still hit something in the compound, but it would at least help protect your most valuable buildings.

-fornit

14

Are we talking about real paint here?

15

No; to “paint” the target means to momentarily illuminate it with the laser beam that the ordinance is looking for, in this case. I’ve heard the term used with other weapons/detection systems and I think it generally means to make contact with your target with whatever your throwing at it in the sense of acoustic waves, electrons, laser beams, etc. Perhaps “mark” would be a synonymous substitute.

16

If the target is being painted by someone on the ground, how does the bomb distinguish between the painter and the paintee?

17

This would be a good idea, were it not for PCM (Pulse Code Modulation) and PIM (Pulse Interval Modulation), by which the actual laser designation of the target is modulated :slight_smile:

18

Since a laser beam is greatly collimated, the beam itself won’t be seen. Rather, the impact point where reflection takes place will be visible. Unless, for some reason, the forward observer were to choose to illuminate the aircraft.