TEL NOF AIR BASE, Israel — When Boeing, Lockheed Martin or any other U.S. airframe provider says something can't be done — or that it must be done in a prescribed manner according to company procedures — Depot 22 of the Israeli Air Force more often than not will come up with a plan of its own.
Take the case of Arrowhead, an F-15B that recently returned to flight operations after a 2011 mishap which prime contractor Boeing — and the Israeli Air Force, at first — had considered a total loss. Next month marks six years since, shortly after takeoff, a flock of pelicans was ingested into one of its engines, sparking a massive fire. The pilot and navigator managed a controlled emergency landing, but the entire back end of the aircraft was burnt beyond repair.
For more than three years, U.S. Air Force officers debated what to do with the 35-year-old two-seater aircraft. Since the entire front end sustained no damage, many favored cannibalizing the cockpit and its avionics in support of other two-seaters in the force. But then specialists in Depot 22 proposed a plan to mate the front end of Arrowhead with the back end of an obsolete single-seater F-15 that had been parked out in the service's desert "bone yard" for the past 20 years.
"When we started this project, we asked Boeing if it could be done, and we didn't get an answer back," Lt. Col. Maxim Orgad, commander of Depot 22's Engineering Division, told Defense News. "So after several weeks went by and still no answer, we contacted them again about our plan to combine two separate aircraft. They said they never got back to us because they thought we were joking."
Specialists in Depot 22 managed to mate the front end of Arrowhead with the back end of an obsolete single-seater F-15 that had been parked out in the service's desert "bone yard" for 20 years.
Photo Credit: Heidi Levine
In a statement, Boeing said that it has enjoyed strong cooperation with Depot 22 over the past 40 years to preserve Israeli readiness of its F-15 fleet and expected to continue working together for another 40 years or more. "We very much appreciate the professionalism and capabilities of this unit, and, at times, we have also learned from it for mutual benefit," the firm noted.
Lt. Col. Haim Mirngoff, aircraft engineering branch commander at Depot 22, estimated in his 16 years with the unit, he's brought "seven or eight" frontline fighters back to life from severe mishaps, including three that were determined total losses by US prime contractors.
In the specific case of the hybrid Arrowhead – whose tail number 122 reflects the former 110 tail number of the burnt out back end with the number of the Depot Unit which gave it new life – Mirngoff said two-seater F-15s provide unique capabilities that are hard to replicate in the service's predominantly single-seat force. "Especially when you're dealing with a two-seater, it's a shame to throw it away," he said.
The maiden takeoff of the hybrid aircraft after it was brought back to life.
Photo Credit: Israeli Air Force
Orgad estimates the entire project cost less than $1 million, all inclusive of labor and spare parts. "Today, to buy an aircraft like this would cost more than $40 million," he noted.
He added, "I don't know of any other air force that works to revive aircraft that others would throw away or, at best, disassemble for parts. But for us, this is our mission. We can't afford otherwise."
Another thing the service can't afford, officers here at Depot 22 say, is time. Each day an aircraft spends here means lower readiness out in the operational squadrons. To that end, officers at Depot 22 maintain close contact with Boeing, Lockheed, Bell and other frontline U.S. suppliers.
But if the manufacturer's plan of action exceeds Air Force-allotted down time, it invariably falls on engineers, aeromechanical and structural specialists, software designers and others of this 1300-strong unit here to devise so-called workarounds.
"We always consult with Lockheed and Boeing. We have an agreement of sharing knowledge and we always have officers that stay in the United States. But sometimes, because our pilots tend to fly the aircraft much more severely than other pilots in the world and our aircraft tend to be much older, we are the first to detect problems. Other times, even when the manufacturer is first to detect problems, we have to devise fixes ourselves," said Orgad.
The officer recounted a specific case, about a year before Israel's summer 2014 Gaza war, involving bulkhead cracks in the Lockheed F-16. "Lockheed put out safety bulletins about the cracks, and said that in order to check to see if there are cracks, we should remove all the fuel in the system first. That would take about a month per plane; and if we had to check all the aircraft, it would have taken years."
Instead of pursuing the Lockheed-prescribed diagnostic route, Orgad said his team developed an ultrasonic testing device, which it used to map the service's entire fleet in less than three weeks. "We developed a workaround that obviated the need to disassemble everything. We were able to check four to five aircraft per day. And once all the aircraft were mapped, we could prioritize which ones had to be dealt with first, while allowing the others to fly."
But that's not the end of the story. According to Orgad, Lockheed Martin prescribed that bulkheads would have to be removed and replaced if cracks were found to extend beyond 8-millimeters. In those cases, it would have taken a minimum of 18-months per aircraft to replace bulkheads.
"We found some cracks like that, but we didn't disassemble and replace. Instead, the engineering branch under Haim [Mirngoff] developed a repair. At first, the manufacturer told us it couldn't be repaired. But Haim's repair not only works, it can be be implemented at the base. No need to bring aircraft here for depot level."
He added, "So in July 2014, when [Israeli Air Force Commander] Maj. Gen. Amir Eshel went, during the war, to the squadron's base, he got a review and saw there was a 100 percent readiness rate. From that base in Ramat David he called my commander here at Tel Nof and praised him for our totally independent maintenance capabilities… If our unit had to wait for the manufacturer to develop a repair, that squadron might have missed the war."
Lockheed Martin declined comment on the matter.
As for the service's newest Lockheed-built F-35 Adir stealth fighters, Orgad said Depot 22 is building a depot-level maintenance facility within its part of the base here at Tel Nof. And while routine flightline maintenance would indeed take place at the Nevatim desert base, depot-level maintenance, will not be done in Italy, as originally planned by the F-35 Program Office, but here, south of Tel Aviv.
"We will not go to Italy or anywhere else. Never. These aircraft will remain in Israel for whatever they need," he insisted.