The A-10 is an incredible and reliable aircraft. However, after 15 years in the Artillery and FO fields, I have to admit: The A-10 relies inordinately upon the good graces of other aircraft and services to survive. Before the A-10 begins its interdiction role (the majority of its work, not CAS), there is a very high level of assurance that all threats have been eliminated. ADA and SAM units are extensively targeted before the A-10 makes it's first flight. That's just the nature of a slow and highly targetable aircraft like the A-10.
There will come a day when we need to target armor in theaters where there hasn't been a visible presence. As in the past, F-16 and F-18 aircraft will perform that role. They get their faster and they don't have the dangerous limitations of the A-10.
In GWI, it was Apache's that cleared the ADA/SAM path for attacking coalition aircraft. The A-10 did not routinely operate in areas of active SAM/ADA. In addition, the lack of targeting equipment (FLIR, Radar) kept the A-10 in the interdiction role more than Close Air Support. The A-10 has to fly low (and slow) to properly identify and engage targets, and this is where it's most vulnerable.
I'm not calling for a retirement of the A-10, RIGHT NOW. But there is definitely a need for an attack aircraft with greater performance and electronics. Hopefully, the JSF (Joint Strike Fighter) will possess the required capabilities.
Couple of comments -
A-10: There is a modification program to give the A-10 digital avionics, data link, targeting pod and the ability to use precision weapons. It is called the Precision Engagement upgrade, and I'm told ACC put it at the TOP of their list to be canceled. The F-16 is more capable at CAS than it used to be - as targeting pods improve, it becomes possible IN CLEAR WX to target with great precision at 35,000 feet. The new targeting pods (Litening and maybe someday Sniper) offer awesome performance. However, in
cr@ppy wx, you have to get low & slow. Not all wars are fought in clear weather!
As for the F-111: it was given an avionics upgrade in the mid-90s that turned it into a highly reliable and very precise aircraft, with operating costs equivalent to an F-15E. It was retired almost immediately after modification. In fact, one of the EF-111s went directly from the mod line in Sacremento to the boneyard in Tucson - one flight post mod.
The USAF could have kept 24 F-111Fs and 36? EF-111s - all modified - for the cost of operating 20 Prowlers...and each Prowler carries (typically) 60% of the EF-111's transmitters. In addition, the EF-111 had been modified to PREVENT it from carrying HARM missiles - the wires to the wing station were cut to prevent competition with the Block 50 F-16s. Had they been spliced, the EF-111 could have carried 4 HARMs and 10 transmitters on every sortie with twice the loiter time of a Prowler - with twice the numbers and 24 F-111Fs thrown in for free...but the USAF killed the remaining 111s while the Navy agreed to fund the 20 Prowlers.
Wish I could be more optimistic about the A-10 surviving - I would like to work on the upgrade - but the F-111 example shows how stupid the USAF can be about their 'second class' aircraft. BTW - when I was an ALO, I loved the A-10 and despised the F-16.