1956 — May 15, Crane Co. PV1 loses left eng. power on AP approach, crashes ~Jeffersonville IN–8

–8 Aviation Safety Network. Crane Co. Lockheed Ventura crash near Jeffersonville, IN, 5-15-1956 –8 Civil Aeronautics Board. Accident Investigation Report. Crane Co. crash near Jeffersonville. Narrative Information Civil Aeronautics Board. Accident Investigation Report (File No. 2-0017) on N 64001: “The Accident “A Lockheed PV-1, N 64001, owned and operated by the Crane Company, crashed near Jeffersonville, Indiana, on May 15, 1956, about 10:38. All eight occupants – six passengers and two pilots – were killed and the aircraft was destroyed by impact. Fire did not follow. “History of the Flight “The flight was for the purpose of transporting six Crane officials from Chicago, Illinois, to Louisville, Kentucky, to attend a business convention. Departure was from O’Hare-Chicago International Airport on a VFR [Visual Flight Rule] flight plan (changed en route to IFR [Instrument Flight Rules)] with the Crane Company’s Chief Pilot Randolph A. Mulherin in command, and Robert H. Robinette, also a Crane pilot, as copilot…. “Shortly after takeoff the pilot gave a routine report to the Chicago radio of his time off as 0908 and his estimated elapsed flight time as one hour and 20 minutes….Other radio contacts followed as the flight progressed, the final one being at 1034 over the Jeffersonville intersection. An approach was then started from that point to the Standiford Airport, 6-9/10 miles distant. During this approach the aircraft struck trees and crashed at a point one-half mile north of the Jeffersonville intersection…. “Investigation “….Testimony of witnesses….varies considerably and is without full consensus. But from it some strong probabilities emerge. First, the engine (s) noise did not sound normal, but was variously described as irregular, labored, or as if backfiring. Second, the aircraft was extremely low, described as just above the trees, twice the height of a silo, etc., just before the crash. The left engine, although described by one witness as stopped, was later found not to be damaged internally, and therefore was free to windmill. Just prior to impact, the aircraft’s speed was low and decreasing with the nose up. The final dive into the ground was abrupt and steep. The private pilot did not see but only heard the aircraft. He deduced, from the change in sound, that during a 360-degree turn, which was made in the general area where a left procedure turn would normally be made, one engine stopped firing and the other ‘….began terrific labor….’ “At the time of this accident Pilot Mulherin had a total on nine PV-1 flight hours, all in the subject aircraft. This nine hours included his rating checkflight with a CAA inspector, which he passed satisfactorily. “Analysis “The final message from the aircraft was at 10:34, four minutes before the crash, and gave no inkling of trouble…. “It appears that after starting the instrument approach…the left engine lost all but idling power. The left carburetor idle control valve linkage fork must have suddenly become disconnected, without warning, at this time. It would normally be at about this time that power changes (throttle movements) would be made and the aforementioned bolt could then have come out. What may well have happened is that Pilot Mulherin changed throttle settings, experienced a sharp yaw to the left due to windmilling of the left propeller, spent the next several seconds trimming the aircraft to offset the resulting drag, and then attempted to determine the trouble. During this short and critical period, to continue with the premise, and at low altitude, the speed of the aircraft continually decreased until control was lost as it struck trees and then dived into the ground…. “As mentioned under Investigation…erratic engine operation and loss of power when flying through rain sometimes occurs and may have occurred to the right engine in this instance. This condition can be minimized by the use of carburetor heat which in effect furnishes, to some degree, sheltered air. In this instance, if such were occurring, it is hardly understandable why the use of carburetor heat was not resorted to. “When the idle mixture linkage became disconnected it appears reasonable to assume that the resultant leaning effect could very well cause erratic sounding engine operation, particularly if throttle movement was resorted to by the pilot in an attempt to restore power. “The fact that the left propeller was not feathered is resolved around two possibilities: One, that a malfunction in the system existed prior to the accident and impact damage precluded any functional testing of the system; and two, that the flight crew did not recognize the need to feather the propeller since the left powerplant instrumentation indicated a near normal engine operation. “Mulherin, although a pilot of long and diversified experience and fine reputation, was nevertheless relatively inexperienced with th subject airplane. The large, open field directly and immediately ahead of the crash site suggests that he may have made an attempt to reach it in lieu of the airport. “Findings …. “2. Pilot Mulherin was relatively inexperienced with the subject model aircraft. “3. The left engine suddenly lost all power because of a disconnected carburetor control. “4. The left propeller was found not feathered. “5. Examination of the right engine revealed no significant defect. “6. Altitude could not be maintained and the aircraft struck high trees and then plunged steeply to the ground. “Probable Cause “The Board determines that the probable cause of this accident was a critical loss of altitude, due to a complete power loss from the left engine and the drag of its windmilling propeller.” Sources Aviation Safety Network, Flight Safety Foundation, Database. Crane Co. Lockheed Ventura crash on approach to airport, near Jeffersonville, IN, 5-15-1956. Accessed 7-6-2023 at: https://aviation-safety.net/database/record.php?id=19560515-4 Civil Aeronautics Board. Accident Investigation Report. The Crane Company, Lockheed PV-1, N 64001, Near Jeffersonville, Indiana, May 15, 1956. CAB File No. 2-0017, Released: February 21, 1957. Accessed 7-5-2023 at: https://www.google.com/books/edition/Accident_Investigation_Report/R_56hjkiZ5IC?hl=en&gbpv=1&dq=File+No.+2-0017&pg=PA1&printsec=frontcover