When it comes to capturing the imagination of old and young, sport fliers and professionals, nothing can beat the appeal of warbirds. Antique biplanes and World War II fighters have been popular for years, and recently the availability of former Eastern Bloc jet fighter trainers has expanded the appeal of very hot airplanes among those who have ridden the stock market (among other things) to riches.
But just as its said that a fool and his money are soon flying more airplane than he can handle, the accident record for warbirds paints a very discouraging picture. Valuable and irreplaceable aircraft, including P-51 Mustangs, hit the ground for reasons that can only be described as irrational, taking their pilots with them. Although accidents involving mechanical failure may be forgivable given the age of the airplanes, often the culprit is buzzing, running out of gas, lack of proficiency or ignorance of the airplanes operating procedures.
For example, an F4U Corsair ran out of gas near New Smyrna Beach, Fla. The pilot was on a local photographic flight when his engine began to sputter, then it quit. He ditched in a lake. Although he claimed to have visually checked the gas tanks and he said the gauges read 120 gallons, investigators found all fuel tanks empty.
In another instance, a pilot flew his P-51 from Fort Lauderdale to Galveston, Texas. He didnt check the weather before he departed and, on arrival, found the Galveston area with a 100-foot overcast and visibility at just one-tenth of a mile. He flew two instrument approaches into Galveston, missing them both. Fuel was critically low and the pilot ditched the airplane in the Gulf of Mexico.
Another almost identical mishap involved a newly acquired British- made Gnat jet trainer. On a delivery flight through the southeast, it also missed a couple of approaches then ran out of gas and crashed.
Part of the problem with fuel exhaustion is that many fighters were designed to use drop tanks, with only limited fuel available without them.
In the P-51D, for example, most owners have removed the 85-gallon fuselage tank in order to install a second seat. Without drop tanks, the Mustang will hold only 192 gallons with the fuselage tank removed. At 65 gph in cruise, the airplanes endurance is less than 2 hours.
Pilots accustomed to the longer ranges of civilian airplanes dont always realize how thin the operating margins are.
Pushing the range of the airplane isnt the only reason fuel-related accidents happen, however. Lack of understanding of the airplanes operating procedures shares the blame.
Perhaps the most publicized fuel starvation mishap occurred to a well-known warbird pilot flying a newly restored P-38. It was especially tragic because the pilots father, who logged more than 3,000 hours in the Lightning during World War II, witnessed his sons fatal accident.
The pilot held a Letter of Authorization from the FAA that allowed him to fly all makes and models of high performance piston powered aircraft. While he was new to the P-38 he had flown a sister ship for about six or seven hours within 90 days of the accident.
On the day of the accident, the owner had topped off the two 44-gallon reserve tanks and the two 72-gallon mains and then had flown for about 20 minutes prior to the fatal flight. The P-38s POH recommends Warm up, take off and fly the first 15 minutes on reserve tanks. This provides space in the reserve tanks for fuel vapor return from the carburetors.
The accident flight lasted approximately 25 minutes and the fuel selectors were found in the wreckage on the reserve tanks. The POH shows that using 2,300 rpm would consume 63 gph. On the reserve tanks alone, the airplane would fly for about 42 minutes. The pilot apparently ran out of fuel on the base leg for landing even though the main tanks were full.
Witnesses said the airplane was much slower than normal while flying the pattern. Then, when the first engine quit, the airplane was going too slowly for the pilot to maintain control.
The POH recommends that if an engine fails below 120 mph IAS, the pilot should close the throttles and land straight ahead. It appeared that the pilot was below Vmc when the engine failed. The aircraft entered a flat spin and crashed. The NTSB determined the probable cause to be failure of the pilot to maintain minimum control speed after loss of power in one engine. Related factors were, The pilots improper fuel management and failure to change the fuel selector position before a fuel tank had emptied, which led to fuel starvation and loss of power on one engine. In addition, the board concluded a contributing factor was the pilots lack of familiarity with the aircraft.
Lack of familiarity and proficiency are big issues in flying warbirds. Even military pilots, supported by maintenance crews and the best training around, suffer pilot-induced accidents. Vintage warbirds, particularly jets, come from a time when the technology was highly developmental, further increasing the odds of failure.
The Checkered Past
Years ago an F-86F Sabrejet ran off the end of 6,000 foot long runway 30 at Sacramento Executive Airport after the pilot rejected the takeoff. The jet collided with several automobiles and crashed into an ice-cream parlor located on a street off the end of the runway. The death toll was 22, with another 28 seriously injured.
The inexperienced pilot had between 3.5 and 7.5 hours in the Canadian-made Sabrejet. His only other jet experience was as co-pilot in a Lockheed Jetstar and Learjet.
According to the accident report, the pilot was limited to two airports – and Sacramento was not one of them. He was there for a two-day airshow. The runway was shorter than he was used to, and witnesses said he rotated to more than three times the normal takeoff attitude during his takeoff run.
When the Sabrejet failed to fly he lowered the nose to build airspeed, then again badly over-rotated. The relatively short runway may have inspired his early rotation, however the NTSB suggested a change in visual cues was to blame. (This same mistake caused numerous Air Force accidents over the years.)
Inadequate training and knowledge of the airplane is a profound problem when it comes to flying ex-military aircraft. Pilots often dont appreciate the fact that, in its military days, the aircraft was maintained by a crew of mechanics who serviced the airplane before and after every flight. Civilian pilots often have no idea how the aircraft systems work, and most likely they have never read the Flight Manual (Tech Order or so-called Dash One). Those who do are generally content to cover only the normal operating procedures.
Little thought is given to memorizing emergency procedures, despite the fact that an in-flight fire or engine failure doesnt leave you time to dig out the Tech Order and find the applicable procedure.
Another problem is the lack of flying proficiency. The problem is complicated among those who prefer fighters, which represent the hottest planes available at the time they were built. Yet pilots routinely get into warbirds with minimal training and little recent experience.
Perhaps they are put off by the high cost of flying a warbird. Perhaps they are busy with other responsibilities and see their warbird as a toy to occasionally take out and play with.
Regardless, the lack of proficiency jeopardizes not only the pilot and any passengers but also the surrounding community. Then too theres the fact that crashing a rare warbird is like destroying a piece of history.
A classic example involved one of the last remaining Martin B-26s. The flight was to prepare a pilot for his Letter of Authorization flight evaluation – in essence a type rating – with an FAA inspector. After takeoff the pilot told Departure they would be working on stalls and steep turns.
Controllers instructed them to maintain VFR at or above 5,500. Shortly thereafter witnesses saw the aircraft at approximately 250 feet agl heading southwest and with both engines sputtering. Then the engines quit and the airplane turned sharply right and crashed.
According to a newspaper article, the PIC was 72 years old. And while the accident report showed him with more than 500 hours in the B-26, he had not flown the airplane for two years. Two days prior to the accident he got (legally) recurrent by flying for half an hour.
The airplane was known to be carrying 720 gallons of 100LL avgas so the double engine failure mystified investigators.
When Cutting Edge Gets Dull
Because of their high-performance, fighters especially are prone to mysterious failures, often of powerplants that were designed in the early days of jets.
For example, a Grumman F9F-2 Panther ran off the end of Kalamazoo/Battlecreek International Airports 6,500-foot runway 35 after returning to the airport with a power problem shortly after takeoff, according to the NTSBs accident report.
The pilot said the aircrafts acceleration on takeoff was acceptable, but the indicated airspeed would not exceed 120 knots – slightly higher than the airplanes normal landing speed. He said that, as he was climbing, he felt a sudden deceleration that threw him forward against his harness. He climbed to about 2,000 feet, stayed in the pattern and called the tower to say he had a problem.
He told investigators that when he was opposite the approach end of runway 35 he retarded power to flight idle, but the RPM remained at 65 percent. He decided to make a dead stick landing and shut down the engine. Final approach airspeed he reported as 140-150 knots indicated.
According to the NTSB report, ATC radar showed the jet screaming toward the runway at a ground speed of 220 knots. A witness reported the airplane was going very fast and looked like it was going to be a high speed pass. At touchdown, the airplane was still going very fast and, halfway down the runway, the skid marks began.
As the skid marks neared the runway end their width and color intensity gradually diminished. The tire tracks continued through the clearway, across an east-west dirt access road, through a chain link fence, up an embankment and across an east-west four lane highway, finally coming to rest on an earthen berm.
One witness who saw the plane coming directly at him told police the aircraft wheels were cherry red as it neared the four-lane highway.
The pilot was seriously injured in the crash, and it took rescue workers nearly an hour to free him from the wreckage.
The pilots logs showed he had flown the airplane for 5.5 hours in June, more than three months before the crash. His logbook showed no other Panther flights in at least the six months prior to the June flying.
The Korean War-era airplane was a cream-puff, having been assembled from new and surplus parts in 1983. The airframe and engine had only 373.4 total hours. The pilot reported about 230 hours in make and model.
In records the pilot supplied to investigators, he showed two hours of instruction in a DeHavilland Vampire 11 years earlier, followed in two weeks by his first flight in the single-seat Panther. He reported his ground school consisted of an hour-long telephone conversation with a former Grumman test pilot.
Before flying the Panther the pilot prepared for acquiring his first jet fighter by flying an hour or so in a Lear 24 and logging the Vampire time. To get experience with a control stick he reportedly flew a T-34. Yet the Lear 24 and T-34 flight times were not included in the logbook entries he provided investigators. The pilot was given LOAs to fly the Panther in 1985, 1986 and 1987.
Investigators uncovered several other factors that could have affected the airplanes power production.
The fuel required for the Panthers Pratt &Whitney J42-P8 engine is JP-3, which is not readily available. Therefore, most warbird owners use a blend of 80 percent 100LL and 20 percent Jet-A.
This formula was given the FBO for the Panther, but refueling records showed that Jet-A was placed in the fuselage tanks and 100LL into both wing-tip tanks. No effort to blend the fuels was noted. Thus the reported slow acceleration during takeoff could have been due to the lower volatility of the Jet-A.
The pilot also reported a history of trouble with the fuel control unit, but investigators found the engine operated correctly after the accident. They also turned up other evidence that improper starting procedures could have added wear to the fuel pumps.
Proper starting procedures stipulate that the fuel pumps must be bled prior to starting any time the engine has been inactive for more than a couple of days because air in the system can cause poor lubrication and cavitation. The mechanics who maintained the Panther said it was not standard practice to bleed the pumps, nor had it been done prior to the accident flight.
The requirement is not reflected in the pilots flight manual, however, because as a military aircraft the Panther would be tended by a maintenance team with its own set of manuals.
While there is substantial evidence that some kind of fuel-related problem caused the power surge, the reason for the erroneous airspeed indication was never determined.
An Ounce of Prevention
A factor that commonly emerges in warbird accidents is the fact that many of the pilots holding FAA approval to fly the airplanes – the LOA – do not meet the FAAs own requirements. Wealthy pilots who can afford the care and feeding of an Aero Vodochody L-39 or a surplus MiG-21 manage to get LOAs with only minimal turbine time, for example.
FAA publication 8700.1, the General Aviation Operations Inspectors Handbook, stipulates that an applicant for a LOA must have at least a Private certificate and be rated in the appropriate category and class of airplane. The handbook further states that someone interested in flying a surplus military jet must have a minimum of 1,000 hours total time, including 500 hours PIC, or must have logged a minimum of 500 hours of flight time and have completed a U.S. armed services qualification checkout.
However, pilots with little or no experience flying jets are managing to secure LOAs that allow them to fly aircraft that were once the countrys first line of defense. Brokers and dealers who sell the airplanes openly offer LOAs in jet warbirds in five to 10 hours of flight time, sometimes with no stipulations regarding experience or proficiency. The LOA can be issued by the same person who gave the pilot training, essentially eliminating any kind of check ride. Once the LOA is issued, its up to the pilot to maintain currency.
A number of schools have sprung up for training in military surplus aircraft. For example a school in Florida has a Mustang with dual controls, in which new or potential P-51 pilots can get a proper ground school and a thorough in-flight checkout. A school near San Diego has a T-28 course that has a great reputation for high quality training.
With professional instruction available there is no reason to issue a LOA to a new owner and inexperienced pilot, unless he has attended one of these professionally run courses for the particular airplane.
Even a well-trained pilot can be at the mercy of the airplane, however. While many of a warbirds systems can be maintained by almost any competent mechanic with the right reference materials, some warbirds have features the mechanic may never have seen before.
Take ejection seats, for example. The FAA allows them to stay hot, provided they are maintained according to the manufacturers specifications. Ask the mechanic who works on your companys Citation if he wants to work around live rocket motors, however, and you may find yourself looking for a new mechanic.
The now deceased owner of an immaculate F-86F Sabrejet learned the hard way that ejection seats are there for a reason. During a high-speed pass over the airfield his engine suddenly seized. Without the engine driven hydraulic pump, the hydraulic flight controls froze.
The plane reportedly had not been flown for several months and the battery was too weak to provide emergency power to the electric hydraulic pump, assuming the pilot knew of this very limited emergency capability.
The warbird accident history shows that new approaches to qualifying pilots to fly hot airplanes may be worth pursuing. Bringing proper experience to the cockpit in the first place is important, as is a thorough checkout in the airplanes handling characteristics as well as its systems.
Annual recurrency training should be mandatory – after all, its required of active duty military pilots. In addition, having an independent examiner give an oral exam and flight check to the LOA applicant would help preclude the buddy system from corrupting the requirements.
Currency is another problem. LOAs should not allow a six-month interval between flights. Some critics of the system say if a pilot goes six months without flying the warbird, his or her LOA should become invalid and he or she should have to re-qualify.
Getting legally recurrent by flying in an air show may provide a nice tax break for aircraft expenses but it is quite hazardous to the spectators.
Warbirds are great fun to fly, but all the rules of training, learning and proficiency still apply. And while flying an aircraft on an experimental certificate gives the pilot/owner exceptional leeway, there is an implied trust involved.
When that trust is violated, as the accidents described show, the lives of innocent spectators are jeopardized. Ensuring the safety of innocent people is a fundamental principle behind many of the regulations now, but some pilots egos wont allow them to think their ability to control an airplane – any airplane – will ever be in doubt.
If they get into a warbird, their testosterone may well lead them to the scene of an accident.
-by John Lowery
John Lowery is a former Air Force pilot and accident investigator and has logged 5,000 hours in fighter jets.