NTSB’s Preliminary Report on the Monck’s Corner Midair Fails to Present Critical Airspeed Data

It took NTSB ten days to release a report on a midair collision that killed two men, when their Cessna was broadsided by a USAF F16 ‘training flight’ north of Charleston, SC [KCHS]. A PDF copy of the report text has been created, and includes footnotes pointing at areas needing further detail and investigation.

As noted earlier on this website, both FAA and NTSB need to become more immediately transparent on serious incidents, especially low-altitude fatal midair collisions. At a minimum, we should be able to see radar presentations (showing positions at key times, as well as datablocks that reveal altitudes and groundspeeds at those times), just as we should be able to listen to a copy of the audio between the F16 pilot and the KCHS approach controller.

What new information was produced? Here are a few key points:

  1. Very significantly, the impact occurred at just 1,500 feet altitude, an incredibly low altitude for an F16 to be passing at high speed near a small general aviation airport (Berkeley County, SW of Moncks Corner, [KMKS]).

    20150720scp.. VFRmap re Moncks Corner midair (showing Shaw AFB E to KMYR S to KCHS)

    VFR sectional showing: F16 departure from KSSC (orange triangle), F16 practice approaches at KMYR (orange square), final destination for F16 at KCHS (orange circle), and approx. route of Cessna from KMKS toward KCRE (red line).

  2. The report notes a 10:20 departure by the F16, a flight to KMYR to conduct two instrument approaches, then a flight to KCHS for another practice approach. Thus, it took just 40-minutes for this F16 to fly 79 direct nautical miles to KMKS, fly two approaches, then fly 63 direct nautical miles to the collision near KMKS. The time used up to fly two practice approaches at KMYR is substantial, thus suggests: this F16 was likely screaming through the sky, and at only 1,500 feet altitude (though interestingly, at the initial press conference on July 7th, the USAF commander said they believe the collision was at 2,500 to 3,000 feet altitude).
  3. Although NTSB provided many valuable details, they made absolutely no mention of a hugely important factor: the F16’s airspeed leading up to the collision. Historically (and this goes WAY back to the almost weekly fatal midairs that happened in the 1960’s, when jets were first introduced commercially), airspeed differentials are a major contributing factor to midair collisions. Certainly a Cessna at just 1,500 feet altitude would have very little opportunity to avoid a fast-moving jet pointed straight at the Cessna. This pattern, with NTSB failing to mention a very pertinent detail in their Preliminary Report, is a repeat of what happened a year ago when a student from Germany was killed in a crash near St. Cloud, MN, for which there was strong evidence an arriving Allegiant flight was too low and too close, creating a wake turbulence upset.
  4. The controller’s handling suggests a systemic ATC aversion against ‘controlling’ military training flights. ATC should never have allowed the F16 pilot to scream along at just 1,500-feet, particularly since the collision was at roughly 18-miles northeast of the runway in Charleston. Typically, a normal stabilized approach descends roughly 300-feet per mile, so a ‘controlled’ civilian flight would expect to be descending through 5,000+ at 18-miles out. Had the F16 flight been properly controlled, ATC would have held the flight higher, to at least 3,000 or 4,000 feet, and with a moderate (even minimal?) airspeed consistent with safe operation of the F16 while mixing safely with low-altitude civilian flights. In the image below, note the TACAN approach is normally flown via a 24-mile arc (much further out) and has a crossing at LADRE at or above 3,000 feet. It appears ATC dove the F16 early to enable the pilot to get under the scattered layer, to conduct a quicker ‘visual approach’ to land KCHS Runway 15.

    Red circle marks the approximate midair location.

    Red circle marks the approximate midair location.

  5. The simple fact is, if this controller had asserted earlier and aggressive control of the F16 flight, or if the controller had NOT told the F16 pilot to turn south (which turn was delayed by the F16 pilot), there would have been no midair collision. I.e., timing and timidity conspired to translate ATC instructions into two fatalities and two destroyed aircraft.

As a former air traffic controller (forced into early retirement due to whistleblowing), I find this incident and the post-incident handling very troubling. Two men lost their lives unnecessarily, but the F16 pilot and the FAA controller were also victim. They have to live with what they saw unfold, and they will forever wonder, what could they have done differently to have prevented this accident?

An FAA that routinely looks the other way while F16 pilots scream at low altitudes is only enabling risky flying that will eventually produce tragic consequences. Frankly, it would not be at all surprising to see this controller retire on a stress-related disability, primarily because FAA is so eager to accommodate aviators, they too often fail to assert real and needed safety controls.

UPDATED 7/20/2015