Page:CAB Accident Report, Piedmont Airlines Flight 349.pdf/5

 approach plate, was in error. rI‘he correct heading should have been 201 degrees instead of 212. The error resulted from not amending the heading when, several months earlier, the course of V—lhO airway was shifted slightly, In this acc1dent the error loses Significance because, according to the ﬂlght plan for Trip 3h9, the correct heading was used. Further, the uSe of tracklng procedures in flight would eliminate the effect of the erroneous heading. Hevertheless, the attention of both the FAA and the company was immediately directed to the error for correction.

According to the instrument approach procedure, upon reaching the CharlotteSVille homer beacon an outbound track of 20? degrees should be flown, normally for l to 1—1/2 minutes. This is followed by a standard procedure turn on the southeast Side of the track. USing the standard procedure turn, the outbound heading is 162 degrees and the inbound heading is 3h2 degrees. The final approach track to the airport is 02'? degrees.

Descent below 3,000 feet is not authorized prior to the final approach; then a descent lS permitted to not less than 2,200 feet before reaching the Charlottesnlle homer. Thereafter, descent may be continued to the authorized comm altitude of 1,039 feet, or [LOO feet above airport elevation.

From the Rochelle intersection the entire instrument approach to landing in the DC-3 takes apprOXimately 15 minutes. From Rochelle to the inbound heading of the procedure turn about 10—11 minutes1 time 18 normally required. It appears important to note that based on the reported time of Flight 31;? over Rochelle, 2025, and the crash time indicated by TI. Bradley, 201:,0, the Eelapsed time was approxzunately 15 minutes.

Although the radio and nangational equipment from N 551? was badly damaged and some portions were destroyed, information which was important to the investigation was available. Examination of the omni equipment dis— closed that both receivers were tuned to 115.3 H1ch the Gordonsnlle omni range frequency. It was also learned that the right omni bearing indicator was set to select the 30l—degree radial or, as prevxously indicated, the radial which passes through the EarlyVille homer. The radial selected on the other unit could not be determined

Examination of the Various components of the red and green ADP units disclosed both receivers were peeitioned to select hand 1, the ZOO—hit) kc. range. It was determined that the red ADF unit was tuned to 265 kcs., oI' appromately the frequency of the Earlymlle homer, 266 kcs. Impact damage to the green ADF made the most reliable indication of the frequency setting the peeition of the frequency selector. This, slightly damaged and locked 19— peeition, was set on 286 kcs., or close to the frequency of the Charlottesulle homer, 28h kcs.

Examination of the ADF loop assemblies revealed that the position of the red ADF loop was equivalent to a bearing of 91 degrees on the cockpit needle: 0n the same 138.513 the green ADF was pOSitioned on a bearing of 112 degrees. The loop pOSitions are most reliable as to the pOSitions of the needles 011 the ass mstrument; however, this cockpit instrument, except the face, was osgtfob’ed' It is Significant that With the aircraft on the crash heading of about 3:47 09'" grass the bearings of 91 and 1.12 degrees extended from the crash Site pass very