10月8日美国中情局所发布的情报动态（CURRENT INTELLIGENCE MEMORANDUM）在分析该飞机失联的原因时并未提到被地空导弹击落，但提到了被空对空导弹击落的可能性。1958年国军在空战中曾用响尾蛇导弹击落过共军飞机（据说这是世界上空对空导弹击落飞机第一例），所以美国人猜测共军可能也掌握了这种武器。
CENTRAL INTELLIGENCE AGENCY
OFFICE OF CURRENT INTELLIGENCE
8 October 1959
SC No. 00342
CURRENT INTELLIGENCE MEMORANDUM
SUBJECT: Apparent Loss of Chinese Nationalist Aircraft Over Chinese Mainland
1. A Chinese Nationalist HB-57D apparently was lost over the Chinese Mainland on 7 October. (CROSSOUT)
2. No further information on the fate of the plane is available at this time. As yet there has been no indication of any communist fighter activity in the area involved at the time reported, and no distress signal was received from the aircraft despite the lengthy period during which it was losing speed and altitude.
3. The aircraft involved was an RB-57D flown by the Chinese Nationalist Air Force on a photo intelligence Mission. This type of aircraft has been used extensively during the past year on similar Missions without mishap despite strenuous interception efforts on the part of the Communists. The altitude at which these Missions were flown was beyond the capability of Mainland fighter aircraft.
4. The apparent loss of the RB-57D is as yet unexplained, although further information may shed light on the incident. Possible explanations for the loss include:
a. Mechanical difficulty.
b. Interception by Communist fighters. This would indicate that the Communists have developed a high-altitude interception capability, possibly using FARMER (MIG-19) type aircraft. This would also at least raise the possibility of Chinese Communist use of air-to-air missiles. Communist high-altitude test flights have been frequent during the past three weeks and there have been two recent attempts at high-altitude interception of missions similar to this one.
c. Defection of the air crew. There have been some defections in the past, but no nationalist air crews have defected in recent years.
5. The loss of this RB-57D may lead to a curtailment of Chinese nationalist collection of photo intelligence over the mainland. Furthermore, if this aircraft did in fact, as it appears, go down on the Chinese mainland, the Communists may try to use the incident as "proof” of US “aggression” even though no United States personnel were on board.
HUNTINGTON D. SHELDON
DIST: White House (Brig. Gen. Goodpaster)
NSC (Mr. James Lay)
State Dept (RCI—for Hon. Hugh S. Cumming, Jr.)
ACSI (Army) (Maj. Gen. John M. Willems)
ONI (Navy) (Adm. L. H. Frost)
ACSI (Air) (Maj. Gen. James H. Walsh)
JCS (Maj. Gen. Robert Breitweiser)