After detection, an enemy bomber would be engaged by long-range manned interceptors and next by a Bomarc missile; if it still survived, the bomber would fly into range of Nike-Ajax and Nike-Hercules missiles.
The Department of Defense announced in late July 1960 that on September 10 it would mobilize an unprecedented number of combat aircraft in a training exercise so vast that it could succeed only if civil aircraft did not interfere. "Airlines will have about eight weeks notice to adjust their schedules and notify their reservation holders," read the DOD news release. "Sky Shield differs from earlier exercises in that it will involve the whole radar and electronics system used in air defense. However perfect any system may be, it cannot be relied upon until it has been thoroughly exercised.
"About 2,000 defensive sorties will be flown," DOD predicted. "Exercise forces will not be armed with nuclear weapons. No live ammunition will be used in any phase of the exercise."
Some 1,000 commercial flights would be delayed or canceled in the United States, and 310 in Canada. Nearly 700 private business and pleasure flights would be squelched. In addition, 31 international carriers would delay arrivals or departures until the all-clear.
On September 10, not 2,000 but 1,129 fighter scrambles were flown by some 360 interceptors against the SAC strike force of B-47s and B-52s, which simulated an "enemy" force of 310 bombers. Of the scrambles, 730 attempted to engage the bombers, while the rest cruised in patrol. Bombers split their missions between high- and low-altitude attacks with the two swarms converging on defenders. The missile force simulated engagements by 52 Bomarc, 254 Nike-Hercules, and 96 Nike-Ajax missiles.
In February 1961, William B. Becker of the Air Transport Association surveyed ATA members on how they had dealt with Sky Shield I: notifying passengers of the shutdown, juggling the rescheduled aircraft and crews, and changing reservations. "Estimated cost figures from only nine of the many air carriers affected totalled approximately one-half million dollars," he wrote. Reports from 14 airlines indicated that Sky Shield I, which had grounded commercial flights for six hours in the early morning, resulted in 182 flight cancellations and 100 schedule adjustments. Flying Tiger Line, which flew cargo at night, was hardest hit.
Nonetheless, Becker reported to the FAA, ATA members would support NORAD: "The airlines will continue to cooperate to the fullest extent where military requirements dictate the necessity. In the event that an exercise of the magnitude of Sky Shield is justified in the future, we strongly urge that a minimum of 90 days’ advance notice be given. The exercise should be conducted on Saturday night-Sunday morning of a three-day holiday weekend."
Pleased with the cooperation from the FAA during Sky Shield I, NORAD’s General Kuter wrote to thank agency administrator Najeeb Halaby, who was already elbow-deep in planning for Sky Shield II. Halaby responded, "I am informed that upwards of 2,500 U.S. and foreign commercial flights and some 125,000 passengers may be affected together with a large number of private pilots. I will be happy…to inform these people of your appreciation for the contribution they are making toward the defense of the North American continent."
One channel Halaby had to pilots was the Aircraft Owners and Pilots Association, which published in the August 1961 issue of its Confidential Newsletter a paragraph about the continent-wide exercise. AOPA’s more comprehensive Pilot magazine did find space to mention general details and grounding requirements in local time zones. "Don’t Forget Sky Shield," it began. "If you’ve planned a flight for Oct. 14 or 15, better look at the clock before you take off."
More than 50 U.S. fighter-interceptor squadrons would participate, including those equipped with McDonnell F-101B Voodoos, Convair F-106 Delta Darts and F-102 Delta Daggers, Lockheed F-104 Starfighters, Northrop F-89J Scorpions, and Douglas F-4D Skyrays. Just over a thousand crews were on full alert. Across the continent some 150,000 airfield and flying personnel and 50,000 more in close support would also play a part, spanning NORAD, the U.S. Air Force, Army, Navy, Air National Guard, and the Royal Canadian Air Force. Navy picket ships and blimps bobbed off both coasts.