Air power and sorties rates

You did most likely notice the seemingly never-ending debate about close air support (CAS) - 'slow mud movers (A-10) or gold plated fast jets?'. I won't cover this in detail or choose a side here, but there's something interesting about it that doesn't seem to get mentioned:

The pro-A-10 argument of persistence over the battlefield and the optimization for slow speeds (resulting in a low cruise speed) push such CAS aircraft into a certain behaviour: It's what originated in the on-demand circling fighter-bomber sand light bombers of 1944, which attempted to meet ground troops' dream of on-demand air support to solve problems they can't solve themselves.They liked this and like this for obvious reasons, but their perspective doesn't show the enormous expense required: You need great many aircraft for this kind of availability.
A CAS aircraft waiting close to the targets for targets of opportunity or a call will self-evidently spend much time of the day waiting. A slow aircraft wills elf-evidently spend much time of the day cruising.
Both of this is detrimental to many sorties per day, no matter how simple the ground crews' job is. Pilots can only fly so many hours per week, even if on drugs, and there's hardly any air force with much more crews than combat planes.

The gold-plated fast jets on CAS missions on the other hand will rarely clock more than three sorties per day either, and the "stealth" variety will quite likely even carry few ground attack munitions per sortie. The larger subset of "multi-role" combat aircraft will likely maintain the ability to switch from CAS to air combat mission during a flight, so they may drop their ground attack mission and go try air combat or even be allocated to something but CAS by higher command altogether.

Fw 190F-2

The historical example of Fw 190F Schlachtflieger and Il-2M Sturmovik units that often flew half a dozen sorties per day (by keeping the distance airfield-targets and the cruise speed in a suitable balance) has few modern representatives. The Su-25 a.k.a. "Frogfoot" is likely the most capable one, with lots of trainer-derived ground attack planes and other moderately effective planes as competition (A-4, AMX and Jaguar are historical examples).
The Israeli Air Force used the approach of maximized sorties/day to make itself felt on the ground during 1967 and 1973 as well. The time for refuelling and loading a flight of Mirage-type ground attack planes was cut down to less than 20 minutes, skipping maintenance checks and ignoring minor technical issues.

It's known from Afghanistan that Su-25s flew about five sorties on regular active days, with peaks of eight sorties on the most intense days.

The debate is usually about slow&low versus fast&high, representing low-tech and high-tech approaches (and it ignores that the supposed slow&low posterchild rarely flies low any more).
I'd rather like to see this discussion to move towards 'many sorties vs. make few sorties count as much as possible'. You will have a hard time modifying a high-tech avionics-defined aircraft for 70 sorties in two weeks. There's simply too much that's bound to exceed the "mean time between failure" in these sorties. Maintenance requirements will keep sorties/day down and the maintenance woes may get worse if you deploy to a "forward" airfield with less well developed facilities.

Public debates are often comparing one aircraft with another, emphasis on "one". This is very much misleading. During the 70's you could have about three F-4F sorties per day in Central Europe, but instead of this you could have bought about four or more F-5E and trained their crews with the same budget. Those planes might have been capable of rather five sorties per day, resulting in a 3 sorties to 12 sorties comparison. Don't pin me down on the exact figures; this example was meant to show the general idea: Never compare a single aircraft with another single aircraft of another type! Compare fleet efficiency!

In regard to CAS I do suppose "sorties per day" in dependence on the distance between airfield and target and in dependence on the mean loiter time is a vastly underappreciated variable.

This is indeed true for considerations of air power in general. You may find the term "fleet efficiency" in many RAND studies, but less so in supposedly professional publications or in dedicated internet forums. One could easily be led towards considering individual aircraft instead of affordable fleet alternatives.
The U.S.Navy almost doubled its achievable sorties rate for naval aviation sometime in the 1990's, almost doubling its naval air power strength. Yet apparently nobody expressed thanks and proposed to cut the quantity of carriers in response, being satisfied with Reagan-era naval air power strength. Hardly anyone had noticed it, so very obscure are sortie rates to public or political discussions.*

I've encountered many people who had a strong belief in air power, often focused on some aircraft or munition type as personification of this belief (many people from the UK seem to be under the spell of the "Brimstone" missile, for example). I've yet to see most of them express an expectation for a certain sorties/day figure or attrition rate; both potentially decisive multipliers for air power's influence on the outcome of a war.

In other words: An air force of 100 perfectly invisible jets capable of firing six 100% lethal silver bullets per day each would not stop much of an army riding in 10,000 Toyota pickups short from overrunning its airfields if not country. Well, unless there's a lot of water in between - which might explain something regarding the British and American attitudes!


*: Flying hours per pilot and year are often obscured as well, even though they're often more indicative of effectiveness than the aircraft type.

P.S.: I know there are sorties rates figure rumours on the internet. I don't cite any other than the Su-25 wartime figure because  the other figures are tricky. Sorties rates depend on version, ground crew, airfield facilities, spare parts availability (especially spare engines and spare radars), distance to target, doctrine, quantity of available air crews per plane, ammunitions expended etc. The rules of thumb are that twin engine planes have lower sortie rate than single engine planes, very new and very old planes have lower ones than mature yet still fit planes, high tech have lower ones than planes with austere avionics. The Gripen and the F-5 are special cases because very simple maintenance was among their design objectives.

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