“As I let off the trigger on my second pass, I saw that the master caution light had started flashing. I looked down into the cockpit and saw that my entire left engine instrument stack was completely lit up. Everything that could be lit up was lit up,” Capt Aaron Cavazos, 75th EFS A-10 Warthog pilot
The A-10 Warthog is the world’s premier close air support (CAS) aircraft, despite the jet having been in service for almost 40 years. Originally designed to thwart the flow of Soviet main battle tanks through the Fulda Gap during the expected war in western Europe, the ‘Warthog’ has evolved into the aircraft of choice for troops seeking air support.
One of the key battlefield survivability features of the A-10 is the unusual location of its General Electric TF34-GE-100 turbofan engines. Their position, high on the aircraft’s rear fuselage, decreases the risk of foreign object ingestion and reduces the odds of flak damage knocking out both engines. The TF34s can also be left running while the aircraft is being serviced and re-armed by groundcrews, thereby reducing turnaround time. Four bolts connect the engine pylons to the A-10’s airframe. The power units also produce a relatively small IR signature, and the direction of the exhaust over the horizontal tail surfaces further shields it from IR surface-to-air missiles (SAMs).
As explained by Gary Wetzel in his book A-10 Thunderbolt II Units of Operation Enduring Freedom 2008-14, since the A-10 has been in combat, several have sustained missile strikes to the engines during operations Desert Storm, Allied Force and Iraqi Freedom, yet they were all able to land safely. More often than not, the A-10’s unique engine location has saved lives. One of them was that of was Capt Aaron Cavazos from 75th Expeditionary Fighter Squadron (EFS).
While deployed in support of Operation Enduring Freedom in Afghanistan, Cavazos and his wingman 1Lt Palan were tasked with providing CAS to two different Special Operation Forces (SOF) elements – a SEAL unit and an Army Ranger squad with USAF STS [Special Tactics Squadron] troops – that were receiving sniper fire.
Cavazos recalls: “Both elements were in radio contact with one another, and had narrowed down the source of the incoming fire to a rocky outcrop at almost 8,000 ft on a 12,000 ft-high mountain. They couldn’t see the shooter but could confirm that the bullets were coming from that spot. We didn’t have any airburst Mk 82s left as we’d already employed them during a previous TIC [Troops In Contact]. Our only remaining bombs were GBU-12s, and the odds of being successful with LGBs weren’t optimal. We came up instead with a plan to put a 30 mm spread over the location. We set up for a shooter-gun attack down the valley. We shot one time and then came back around, having covered half the outcrop on the first pass.
“As I let off the trigger on my second pass, I saw that the master caution light had started flashing. I looked down into the cockpit and saw that my entire left engine instrument stack was completely lit up. Everything that could be lit up was lit up. As I continued to egress away from the target area, the left engine RPM had dropped to less than 20. That told me the situation with the powerplant was catastrophic. With the nose of the jet now approaching the horizon, I checked to make sure that my left engine fire handle was on, which confirmed that all my engine instruments were indeed working and that the TF34 was actually on fire.”
Cavazos continues: “By the time I’d completed my safe escape from the area I was 30 degrees nose high. I traded all my excess airspeed for whatever altitude I could get, as I was surrounded by huge mountain peaks. The engine RPM was at zero and the engine temperature gauge was already pegged as high as it could go. If you have an engine failure it usually windmills, but in this case the motor had totally seized. Nothing was turning. By this time I pointed the jet further down the valley towards the only spot where I could eject without hitting rocks when I landed. I could have jettisoned all my stores – two GBU-12s, a rocket pod and two Maverick missiles – but I was flying over friendly positions, as well as civilian houses in the valley. I couldn’t have lived with the idea that my ordnance had hit friendlies on the ground, so I continued flying, trying to gain as much altitude as I could.
“As I approached the ridgeline I noticed that it wasn’t moving down – I was not going to clear it. In a first for me, I put my hands on the ejection handles and prepared to punch out. I waited a few more seconds so as to make sure I knew what I was going to do.
“By this point 1Lt Palan was done with his strafing run, and the JTAC was calling good hits on his attack. No one knew what was going on with me. I looked back and could see smoke trailing from my engine. Through my HUD, I noticed the ridgeline in front of me was starting to sink a little bit, which meant I could probably clear it if I managed my energy just right – I decided to stick with the jet. When i passed over the ridgeline my radar altimeter hit 40 ft. Once on the other side of this mountain, I pushed forward on the stick, trading altitude for airspeed. Only then did I call out to my wingman, telling him what was going on. I also checked in with the ground forces to confirm that they weren’t taking fire any longer.
“Now that I was finally clear of the immediate danger, I pointed the jet back in the direction of Kandahar – it would be an hour-long flight. At this point I was finally able to shut the engine down. I hadn’t done this earlier as it was still producing thrust, even though it was burning. I needed every bit of thrust I could get in order to clear that ridgeline. My wingman did a battle damage check. The engine was done burning so, as I approached Kandahar, I decided I’d jettison my load-out as we had an area to do this south of the base – if I hadn’t jettisoned my ordnance I’d have landed well short of the runway. I put the jet up on the right wing on my downwind so I could let off on the rudder a bit. By the time I was liked up on final approach I had to emergency extend the undercarriage as all the gear extension in the A-10 is powered by the left engine. As I rolled out along the length of it, I could see a two-ship of A-10s waiting for me to get off the runway as they were heading out to respond to a TIC.”
Cavazos concludes: “Once on the ground I was able to reach in and pull pieces of my engine out. There was only one hole in the cowling where a fan blade had punched through it. The next day I flew the same jet again! Maintenance had put a brand new engine on it and the ‘Hog’ was ready to go. The external mounting of that engine saved that jet, and maybe me too.”
Photo credit: U.S. Air Force
Artwork courtesy of AircraftProfilePrints.com