MacIntyre exercised his prerogative as squadron commander to fly the unit’s first combat mission on 17 December. He was not, however, the first Marine aviator to pilot a jet in combat. That distinction went to Captain Leslie E. Brown on 9 September 1950. Assigned to the Fifth Air Force’s 8th Fighter-Bomber Squadron as an exchange pilot, he made the first of several routine flights with an F-80 Shooting Star. On 20 December, 17 officers and 51 enlisted men arrived at K-9 to boost VMF-311’s total to 27 officer pilots and 95 enlisted men. Under Fifth Air Force control, they were employed to attack suspected CCF troop shelters, entrenchments, and gun positions on the eve of the expected enemy offensive. Missions of the jet planes averaged 12 a day at the end of the month. _The Air Force System of Control_ It was seldom realized in the middle of the twentieth century that for the first time since the Middle Ages, a single human being represented in his person a decisive tactical unit. Just as the mailed knight on his barded charger had ruled the battlefields of the medieval world, so did the pilot of a modern aircraft have the power to put an enemy battalion to flight with napalm, or to knock out an enemy stronghold with a 500-pound bomb. [Illustration: MAP 3 COMBAT AIR BASES KOREA-JAPAN] A great deal depended, of course, on how the lightning of this human thunderbolt was controlled. The Marine Corps and the Air Force had different ideas on the subject. At the foundation of the Marine system was the concept that the needs of the ground forces came first, and control of air support should be exercised by the troops being supported. In each Marine infantry battalion a tactical air control party (TACP) included two aviators--one to be employed as a forward air controller (FAC) at the front, and the other as an air liaison officer in the battalion supporting arms center (SAC).[20] [20] The material in this section is derived from the following sources: _PacFlt Interim Rpt_ No. 2, II, 463–620; Chief. Army Field Forces Headquarters, Tactical Air Command, Joint Training Directive for Air-Ground Operations; and CMC, ltr to Dist List re “Analysis of CAS Systems,” 19 Aug 52. In an emergency both could quickly be assigned to companies or even platoons to “talk” air strikes down on the enemy. The normal chain of command was bypassed in favor of direct radio from the TACP to the cognizant air control agency that had the authority to cross-check the request for possible conflict with other operations and to channel fighter-bombers to the attack. Intermediate commands kept themselves informed of the over-all air picture and controlled the employment of aviation by their own subordinates as they listened in on these requests. They indicated approval by remaining silent, and disapproval by transmitting a countermand.