Just prior to the Summit, a working group of approximately 40 people, including CAS-experienced Air Force service members, met for three days at Davis-Monthan Air Force Base to identify potential risks and shortfalls in CAS capabilities. But Air Force headquarters gave them two highly restrictive ground rules: first, assume the A-10s are completely divested, with no partial divestments to be considered; and second, assume the F-35 is fully CAS capable by 2021 (an ambitious assumption at best). The working groups included A-10 pilots, F-16 pilots, and Joint Terminal Attack Controllers (JTACs), all with combat-based knowledge of the CAS platforms and their shortfalls and risks. They summarized their findings with slides stating that the divestment would “cause significant CAS capability and capacity gaps for 10 to 12 years,” create training shortfalls, increase costs per flying hour, and sideline over 200 CAS-experienced pilots due to lack of cockpits for them. Additionally, they found that after the retirement of the A-10 there would be “very limited” CAS capability at low altitudes and in poor weather, “very limited” armor killing capability, and “very limited” ability to operate in the GPS-denied environment that most experts expect when fighting technically competent enemies with jamming technology, an environment that deprives the non-A-10 platforms of their most important CAS-guided munition. They also concluded that even the best mitigation plans they were recommending would not be sufficient to overcome these problems and that significant life-threatening shortfalls would remain.