Most pilots, at one time or another, have experienced a “black-hole” approach or departure — a nighttime phenomenon that, if gone unrecognized, can lead to disaster.

At the close of a recent investigation, the NTSBurged pilots to review the FAA’s Pilot’s Handbook of Aeronautical Knowledge on the subject of night operations. (You can download the entire handbook at no cost from https://www.faa.gov/regulations_policies/
handbooks_manuals/aviation/phak/media/pilot_handbook.pdf)
A black-hole approach, writes the authors, occurs when the landing is made from over water or non-lighted terrain where the runway lights are the only source of light. Without peripheral visual cues to help, pilots will have trouble orientating themselves relative to the ground. The runway can seem out of position (downsloping or upsloping) and, in the worst case, results in landing short of the pavement. If an electronic glideslope or visual approach slope indicator (VASI) is available, it should be used. If navaids are unavailable, careful attention should be given to using the flight instruments to assist in maintaining orientation and a normal approach. If at any time the pilot is unsure of his or her position or attitude, a go-around should be executed.
Credit: Google Earth

The Handbook also suggests that to fly a traffic pattern of proper size and direction, the runway threshold and runway-edge lights must be positively identified. Once the airport lights are seen, these lights should be kept in sight throughout the approach. Distance may be deceptive at night due to limited lighting conditions. A lack of intervening references on the ground and the inability of the pilot to compare the size and location of different ground objects cause this. Similarly, the lack of visual references also applies to the estimation of altitude and speed. Consequently, more dependence must be placed on flight instruments, particularly the altimeter and the airspeed indicator.
According to the Handbook, “The altimeter and VSI should be constantly cross-checked against the airplane’s position along the base leg and final approach. A visual approach slope indicator (VASI) is an indispensable aid in establishing and maintaining a proper glidepath.”
Of course, the NTSB and its predecessor, the Civil Aeronautics Board (CAB), have expressed their concern over black-hole approaches and departures regularly over the years because they have brought to grief pilots of all experience levels operating all types of aircraft.
The black-hole hazard surfaced most recently as the NTSB looked into the loss of N7MC and its two-man crew. The Beech 65-A90 King Air was owned and operated by the Saint Tammany Parish (Louisiana) Mosquito Abatement District and operated under FAR Part 91 as a public aircraft. Its mission was nighttime spraying for mosquito abatement.
The circumstances of the accident are consistent with the pilot experiencing the black-hole illusion, which contributed to him flying an approach profile that was too low for the distance remaining to the runway, said the Safety Board. Credit: Google Earth

Two of the district’s aircraft were in the air on April 19, 2016, about 2100 local time. N7MC was on a spray mission and the second aircraft was flying practice GPS approaches to Slidell Municipal Airport (ASD), the company’s home base. Everyone flying locally that night agreed the weather was perfect. The Slidell ASOS facility reported calm wind; visibility, 10 mi.; clear sky; temperature, 68F; dew point, 64F; and a barometric pressure of 30.09. Astronomical data from the U.S. Navy Observatory indicated that the moon rose at 1730 and set the following morning at 0541. The moon disk illumination was 94%.
After completing their spray mission, N7MC’s pilots radioed on CTAF their intention to land at ASD. The accident pilots said they would fly a visual pattern to Runway 18. The other company airplane was behind them conducting a practice GPS approach to Runway 18. When the pilot of the GPS airplane radioed that they had crossed the GPS approach’s final approach fix, the pilot of N7MC radioed that they were on the left base leg and were No. 1 to land at the airport.
Investigators determined the airplane initially impacted two 70-to-80-ft.-tall towers that suspended high-voltage electric transmission lines. Credit: NTSB

Seconds later, the pilots of the GPS airplane saw a blue arc of electricity, followed shortly after by a plume of fire. They tried to reach N7MC by radio with no success. Then the GPS-airplane crew notified emergency personnel. The wreckage of the King Air was located in a marsh about 0.6 nm north-northwest of the approach end of Runway 18. The pilots were dead. The time was 2115.
Investigators determined the airplane initially impacted two, 70-80-ft. towers that suspended high-voltage electric transmission lines. The lines generally ran on a heading of 150 deg./330 deg. and, due to their height, were not required to be illuminated. Ceramic isolators were shattered on the northern pole, and the top guide wire was damaged on the southern pole. A portion of the airplane’s lower chemical tank and left wingtip were found directly beneath the poles. The airplane’s debris path followed a 175-deg. heading in marshy terrain for about 555 ft.
The main wreckage consisted of the metal hopper tank frame, the upper portion of the fuselage, cockpit instrumentation, inboard left wing, outboard right wing, left horizontal stabilizer, vertical stabilizer, rudder and the left engine with its propeller. A post-impact fire consumed a majority of the cabin structure. The airplane’s nose was generally aligned with 350 deg. magnetic, and the fuselage was inverted.
Flight control continuity was confirmed to all surfaces. The flaps were in the retracted position. The elevator and rudder trim positions could not be determined due to impact damage. The fuel selector position could not be determined. The emergency locator transmitter (ELT) was still attached to the airplane and the antenna and was found in the “armed” position, but it was thermally damaged. The company pilots in the other airplane reported that they did not hear any ELT beacon.
Both pilots’ restraint hardware remained latched; the webbing was consumed by fire. The left fuel-flow gauge read 400 lb. per hour and the right fuel gauge read 250 lb. per hour. The cockpit instrumentation was impact and thermally damaged and was largely unreadable. The right inlet turbine temperature gauge read about 700F. The left propeller speed read about 1,100 rpm.
The right engine was separated and found upright. Its propeller remained attached to the engine. Two of the three blades displayed S-bending with nicks on their leading edges. Examination of the left propeller blades found one blade almost completely consumed by the post-crash fire. Another blade was partially consumed and displayed curling with a rearward bend. The third blade was curled and bent rearward. No anomalies were detected with the airframe and engine.
A thermally damaged SD card was recovered from the airplane’s ADAPCO Wingman GX system and sent to the NTSB laboratory for data extraction. Due to the damage sustained in the accident, the chips on the card were not recoverable.
Experienced Night Crew
The crewmembers of N7MC were highly experienced night flyers. The 59-year-old left-seat pilot held a commercial pilot certificate with ratings for airplane single-engine land, airplane multiengine land and instrument airplane. In addition, he held a flight instructor certificate for airplane single-engine and instrument airplane. He had a second-class medical certificate, dated Feb. 18, 2016, with the limitation that he must wear corrective lenses for near and distant vision.
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The pilot had accrued over 6,800 hr. of single-engine total time with 50 hr. logged in the preceding six months, and 952 hr. of multiengine total time with 15 hr. logged in the preceding year. His flight time in the Beech C90 was 15 hr. with 5 hr. logged in the preceding year. It is estimated that he had 7,762 total hours with 1,135 hr. of nighttime, 10 hr. of actual instrument time and 305 hr. of simulated instrument time. On July 1, 2015, the pilot was approved by the aerial operations supervisor to act as pilot-in-command for the accident airplane and a Britten-Norman BN-2T Islander.
The 68-year-old pilot in the right seat held an ATP certificate with ratings in airplane single-engine land, multiengine land, rotorcraft-helicopter, and instrument airplane and helicopter. He also held a commercial certificate for airplane single-engine sea and a flight instructor certificate for airplane single-engine and multiengine, rotorcraft-helicopter, and instrument airplane and helicopter. He, too, had a second-class medical certificate, with the limitation that he must have available glasses for near vision.
He had accrued 4,310 hr. of single-engine total time with 50 hr. logged in the preceding six months and 5,910 hr. of multiengine time with 105 hr. logged in the preceding year. His flight time in the Beech C90 was 627 hr. with 59 hr. logged in the preceding year. It is estimated that he had 18,163 total hours with 4,619 hr. of nighttime, 2,199 hr. of actual instrument time and 431 hr. of simulated instrument time.
The right-seat pilot also was the department’s aerial operations supervisor. He had worked for the District operation for 31 years. Although he was the more senior pilot, he was seated in the right seat and would have been performing copilot duties, according to other company pilots.
Both pilots had flown the accident airplane together on April 4, 7, 8, 11 and 18, 2015, for a total of 6.9 hr. Each flight ended in a night landing to ASD. On the forms for each of the flights, the area for “comments and/or mechanical problems” was blank.
The accident airplane was originally manufactured as a U.S. Army U-21D in 1968. It remained in military service until 1995 when it was sold to a civilian company. In 1998, the airplane was registered with the FAA as a Beechcraft 65A90-1 and issued a special airworthiness certificate for restricted use for the purpose of agriculture and pest control. The airplane was acquired by the Saint Tammany Parish in June 2012. It was equipped with a radar altimeter and had controls installed in both pilot seats. The airplane’s most-recent inspection was a combined Phase I through IV and annual inspection recorded on Dec. 1, 2015, at an airframe total time of 15,189.6 hr. On that date, the left engine had accrued 9,676.6 hr. since new and 1,638.4 hr. since overhaul. The right engine had accrued 7,413 total hours since new and 1,248.5 hr. since overhaul.
Findings
Safety Board investigators determined the left-seat pilot typically operated the airplane. During the night visual approach to landing at ASD, the airplane was on the left base leg and overshot the runway’s extended centerline and collided with power transmission towers and then impacted terrain. Examination of the airplane revealed no pre-impact anomalies that would have precluded normal operation.
Both pilots were experienced with night operations, especially at their home airport.
“The pilot flying had conducted operations at the airport for 14 years and the copilot for 31 years, which might have led to crew complacency on the approach,” said the safety board. “Adequate visibility and moon disk illumination were available; however, the area preceding the runway is a marsh and lacks cultural lighting, which can result in black-hole conditions in which pilots may perceive the airplane to be higher than it actually is while conducting an approach visually.”
The circumstances of the accident are consistent with the pilot experiencing the black-hole illusion, which contributed to him flying an approach profile that was too low for the distance remaining to the runway, said the safety board.
“It is likely that the pilot did not maintain adequate crosscheck of his altimeter and radar altimeter during the approach and that the copilot did not monitor the airplane’s progress; thus, the flight crew did not recognize that they were not maintaining a safe approach path. Further, it is likely that neither pilot used the visual glidepath indicator at the airport, which is intended to be a countermeasure against premature descent in visual conditions.”
The formal probable cause finding: “The unstable approach in black-hole conditions, resulting in the airplane overshooting the runway extended centerline and descending well below a safe glidepath for the runway. Contributing to the accident was the lack of monitoring by the copilot allowing the pilot to fly well below a normal glidepath.”