Investigation Summary
The aircraft was cleared to descend from FL110 to FL60 while approaching the Dunsfold VOR. The crew acknowledged the clearance and reported passing FL145. However, the Caravelle did not level off at 6,000 feet. Instead, it maintained a shallow, steady rate of descent for 13.5 minutes until it struck trees near Black Down House at approximately 900 feet above sea level. The aircraft then careened across a meadow, where 65 sheep were killed outright and another 23 were fatally injured, before destroying a garage and damaging the roof of Upper Black Down House. The investigation focused heavily on the three-pointer altimeter design. These instruments featured a cross-hatch warning indicator that appeared below 10,000 feet, but investigators noted that the constant motion of the pointers during a long descent could lead to a 'mental loss of sequence,' where a pilot might misinterpret 6,000 feet as 16,000 feet. The aircraft, MSN 202, was manufactured in 1966.
Final Conclusions
The official investigation concluded that the accident was due to the aircraft continuing to descend through its assigned flight level down to the ground. No evidence was found of pre-impact mechanical failure, engine defect, or structural deficiency. While the possibility of altimeter misreading was explored in depth, the board could not definitively prove it occurred, as the crew had correctly reported passing FL145 earlier in the descent. The ultimate cause for the continued descent remains undetermined.
Video Analysis
What Happened to Iberia Flight 062? | The Mystery of the Blackdown Air Disaster 1967 — A detailed look at the 1967 Blackdown air disaster, featuring local accounts from first responders and an analysis of the Caravelle's mysterious descent into the Sussex hillside.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Crew Experience
Captain
Hernando Maura Pieres, age 37. Had flown the Málaga-London route over 100 times.
First Officer
José Moreno Ahumada, age 40.
Flight Engineer
José María Álvarez Menéndez, age 55.
Systems & Failure Modes
Three-pointer Altimeter
A flight instrument that uses three separate needles to indicate altitude; known for being prone to misinterpretation by 10,000-foot increments. The investigation focused on whether the crew misread 6,000 feet as 16,000 feet.
Flight Recorders
A cockpit voice recorder (CVR) and flight data recorder were recovered. While the CVR revealed no unusual activity or alarms, the investigation was significantly hindered because the flight deck instruments, including the altimeters, were too badly damaged by the impact to provide physical evidence of a mechanical malfunction.
Interesting Facts
- 01The crash killed 65 sheep instantly and fatally injured another 23 in a meadow at the impact site.
- 02Among the 37 fatalities was British actress June Thorburn, who was five months pregnant at the time.
- 03The aircraft was named 'Jesus Gurudi' after a Basque composer.
- 04The investigation found the cross-hatch warning on the altimeter would have been visible to the crew for 9.5 minutes before the crash.
- 05The victims included 25 British nationals, 9 Spanish (including 7 crew), 2 Americans, and 1 Australian.
- 06The accident is recorded as the 11th worst aviation disaster in the United Kingdom.
Safety Actions & Advisories
Navigation Beacon Installation
It is suggested that the air navigation beacon at Northchapel was introduced following the disaster to improve regional navigation, although beacons provide position rather than altitude data.
Known Controversies & Unanswered Questions
Three-Pointer Altimeter Design
Reference ↗The investigation highlighted a long-standing industry debate regarding the safety of three-pointer altimeters. While the instrument included a cross-hatch warning for altitudes below 10,000 feet, investigators argued that the warning could become ineffective during a long descent due to 'mental loss of sequence.' The crew's report of passing FL145 proved they initially knew their altitude, yet they still descended into the ground, leading to disputes over whether the instrument's design was a primary factor despite the lack of physical evidence from the wreckage.