Historical rarity of close air support

[Guy w/gun]

On the history channel, a gentleman who was an ex-Hitler Youth was accounting a combat expirience. He said that he and others were waiting on a bridge to ambush an approaching American tank. They succeded in knocking it out with their panzerfausts, but in doing so they provoked an air attack.

So in this case, it would seem that the Americans called in air support in direct response to the tank being destroyed. The bridge was probably of tactical importance, and they saw the need to flush out the ambushers. My question is whether this was the norm or an exception.

Current consensus on air support in CMBO seems to be that in WWII it was unreliable, and not all that available on a tactical level. And in CMBO, you can't "call in" air support. It has to be bought before a QB or pre-placed by the scenario designer. The situation mentioned above seems to suggest the opposite.

:confused:

[ 08-16-2001: Message edited by: Guy w/gun ]

[Guy w/gun]

OOPS! double post

[ 08-16-2001: Message edited by: Guy w/gun ]

[lcm1947]

Well, I'm no expert but I believe that there wasn't that much air support available in WWII period. I would take that interview to be just one incident , meaning it didn't happen alot on that level and the tank had nothing to do with it but maybe the bridge was important and therefore caused the air strike. But as I said I really don't know but this bump might bring out those that do know.

[Michael Emrys]

Close support in the ETO was rare and not always welcome when it did appear, for reasons fairly accurately modeled in CM, though it did improve somewhat as the campaign wore on and everybody acquired more experience. After the Cobra breakout, armored spearheads often had a tank with a ground control officer to call up any handy cab rank jabos to handle pockets of resistance, but it isn't as if they were covering the entire front. I notice that the same thing occurred during Market-Garden. I believe the Rhine crossings were well covered in this way. But these operations were planned for. Day to day coverage was not of the same intensity. Most of the tactical airpower was used in battlefield and deep interdiction, not close support.

Close support was more commonly encountered in the Pacific, where the Marines raised it to a high art.

Michael

[MikeyD]

I recall a PBS documentary where an experienced thunderbolt pilot discribed spending time as as a close air support ground controller on the front lines. The least resistence he saw through his binoculars (perched atop a Rhine castle!) was immediately delt with. It sounds like when the troops had close air support it could be very effective, when they didn't they definitely didn't.

[Slapdragon]

I would be extremely careful about using any single account to generalize, but CAS was available with more than a thousand planes assigned to Cab Rank CAS work over the front by wars end (which means maybe fifty or so up in good weather at a time, maybe less). CAS was designed to break up enemy pockets, terrorize defenders, knock out reinforcements, and the like, but on the scale of CM it would appear much more random.

In the US Army, all tanks and infantry could theoretically talk to CAS through the communications net or through battalion level communications assets, but usually only special controllers worked directly with the planes. In terms of CAS, more than likely the appearence of a plane represents a resource called in by the Regiment or Division to "help you out" and is thus out of your control.

[tss]

Guy w/gun wrote:

The situation mentioned above seems to suggest the opposite.

There's one important thing missing from the account: how long afterwards did the plane attack?

If the attack came, for example, two hours after the tank kill, it could still be a direct response and Germans could identify it a such but in CM scale the scenario would be over long time ago.

I once read an account that went like this: "A faustman hit a Soviet 2-turret tank of an unknown type [actually a lend-lease Grant] immobilizing it. He then crawled near and set it on fire using a Molotov coctail".

By that account, it seems that it would take at most 4-5 CM turns to accomplish that.

However, another account mentions that between the two attacks on the tank the Soviet tank crew actually dug their vehicle in. I'm not certain how long it takes a Grant crew to entrench their vehicle, but I would be very surprised if it could be done in less than 5-6 hours.

- Tommi

[JasonC]

If you analyse an expected likelihood of close air support to finer and finer levels of detail, you can get anything between a bunch of certainties where it did happen and no chance results where it didn't, imagining perfect info. The more you average over situations, regarding them as similar, the less clumpiness you'll see. At the top, you can look at an overall average, which washes out any data there might be about whether this or that is a more likely time, place, or situation to get close air support. With that qualifier in mind, we can talk about constraints on the -average- chances of a unit of a given size receiving CAS of a given size.

Fighters flew on the order of 1.2 million sorties in the campaign in the west. At least half of them were bomber escort missions, while the most common role after that was interdiction, aka "armed recce" over enemy transportation lines. The rest were split about evenly between attacks on pre-determined, stationary targets, and true CAS missions. This process of subdivision crudely gives an estimate of 150,000 total CAS sorties for the war in the west. Which means on average around 450 per day. It would be higher on the days missions were possible, with overcast preventing any on others. Say 600 per flying day.

Then consider the size of the forces to support, and the length of times the support might arrive. The force size rose over the course of the war. Around 20 divisions were in the line in the Normandy attrition stage. More like 60 at the westwall, and more still by the time the fight was inside Germany. Over the same time period, the Luftwaffe was declining in effectiveness, allowing more of the fighter effort to go to attack missions. 50 divisions in the line will serve as a decent estimate of the forces to be supported - it being understood there are fewer at first but more escort missions, and more later but also more strike missions to spread among them.

50 divisions fighting in standard 2 up, 1 back deployments will mean around 200 battalions in the line. There are 3 sorties per day for each one, on average. But there are also 24 half-hour periods in daylight (less in winter, more in summer, yada yada, close enough). That gets us down to 1/8th of a CAS sortie per battalion in a given half hour on days clear enough to fly.

But CAS isn't flown by single planes, most of the time. The point is that some portion of the sortie count is "soaked up" by the bigger cases, where a squadron or whole group helped the same unit. Leaving fewer instances of CAS received than of total sorties. Correcting for this with a crude approximation for the likelihoods of support of different sizes (2 planes often, 1 or 4 also often, 12 rare and 36 very rare e.g), the chance of a given battalion getting support in a given half hour on a clear day, might be more like 3-5%. For a company, more like 1-2%.

Another way of looking at the same figures would be to compare the volume of support from air to the volume of support from organic artillery - since CM makes them alternatives in the "artillery" point category. A typical US division fired half a million shells from its organic arty (not counting corps and army level stuff). A 100-round 105mm module would be about 18 times as likely as a single fighter-bomber, or perhaps more realistically, a 3-FO battalion shoot (300 rounds) around 12 times as likely as a pair of them.

So, in typical CM scale fights, you'd expect single digit percent chances for air support vs. near certainty of artillery support of some kind. The artillery had a response time of minutes and one battery could fire a ton of ammo at the enemy in under 5 minutes, and keep it up for hours on end when necessary. A CAS sortie of similar "weight" could be flown once a day.

The place that tac air had a significant edge over the artillery was when it could see targets and the artillery could not, and out of their range. That was rarely the case with units in contact - they see for either, and arty is not far behind them. The specific added ability of the planes was their ability to identify point targets in enemy rear areas that could not be observed to call down arty on them, and beyond the range arty could reach. They did need to be able to see the targets despite camo and pick them out of a vast countryside, however. That is easiest to do for things moving along well-defined, easily spotted routes. This also minimized the chances of friendly fire incidents.

That is why interdiction, aka "armed recce", made sense as the main strike mission for tac air. Along rail lines or roads, the search area is much smaller and can be traversed linearly. Moving vehicles are hard to hide; motion attracts the eye very well. Tac Air could hit targets artillery could not, and with much clearer location of the right target area, on such missions. It had no such advantages over artillery when units were in direct contact, and a lower "thruput" capacity, in weight per unit time. Trains and truck convoys were the targets of choice. The efforts expended on CAS produced a smaller result for the same effort, and results more easily achieved by other arms.

[Chad Harrison]

the chances of CAS showing up "on call" like that were a lot more likely hapenning when it was part of a grand scale assult; ie D-Day, Cobra, Market Garden, ect. when the large scale assults were planned out in advance, the chances of having a plane "show up on call" were much greater. for the CM scale, this is something that the scenario designed could represent by just assigning a jabos to "arrive" on a certain turn.

[MikeyD]

I'm actually rather fond of CM's method of CAS. The arrival of that plane-shaped shadow is always great fun. The ability to pinpoint where it should strike would be less-than-historically accurate, and you would also loose that moment of surprise when it flashes by.

By the way, does anyone know what ground speed the plane's shadow is modelled for? I'm guessing 200 mph?

[gatpr]

Wasn't the expression "death by Jabo" a very common one on the Wehrmacht in 1944-45. That supposes a certain level of air support. It does kind of beg the question How close is close?

[Michael Emrys]

<BLOCKQUOTE>quote:</font><HR>Originally posted by gatpr:

Wasn't the expression "death by Jabo" a very common one on the Wehrmacht in 1944-45. That supposes a certain level of air support. It does kind of beg the question How close is close?<HR></BLOCKQUOTE>

Again, I think this mostly referred to highway interdiction against troops on the move. In this form it could be fairly deadly, whereas it took a lot more to discomfit troops dug in to their positions and dispersed.

Michael

[Massattack]

Like MickeyD I think CMBO have done a very good job modelling CAS. The uncertainty of wether you will get a strike or not, the distinct possibility it will cause you harm as well as the enemy. Not sure if it would be possible to time the passage of the Jabo shadow across the known width/length of the map to arrive at a groundspeed for the aircraft, but in theory this should be possible.