Single Engine Considerations

STORY BY LT JOHN LYLES, VFA-94

An F/A-18 Hornet assigned to the Mighty Shrikes of Strike Fighter Squadron Ninety Four (VFA-94), flies over the Western Pacific Ocean during flight operations.( U.S. Navy photo by Mass Communication Specialist 3rd Class Elizabeth Thompson)

An F/A-18 Hornet assigned to the Mighty Shrikes of Strike Fighter Squadron Ninety Four (VFA-94), flies over the Western Pacific Ocean during flight operations.( U.S. Navy photo by Mass Communication Specialist 3rd Class Elizabeth Thompson)

Single engine considerations are discussed in depth in the F/A-18 community. Around the boat we place emphasis on emergency catapult fly-away, emergency gear extensions, and single engine recovery procedures. Ashore, operating in the R-2508 of eastern California, the divert field is often predicated on whether an engine fails east or west of the Sierra Nevada Mountains. I thought I had a good handle on single engine considerations until I had an engine fail while in port observation on a KC-135 over Northern Iraq.

The flight that day began like all the rest. After executing the first vul of close air support, I exited the area as a single for yo-yo tanking and climbed to rendezvous with the KC-135 at 26,000 feet. After a few moments in port observation, I began to hear the thumps and bangs associated with an engine stall, followed shortly by a loss of thrust and the aural “engine right, engine right”.

With a quick glance to my left display, I confirmed the engine stall suspicion with an R ENG STALL caution displayed and I executed the immediate action item of placing the right throttle to idle. The engine stall cleared which was verified through normal engine indications and the removal of the R ENG STALL caution. Given my altitude and configuration, I elected to advance the throttle in order to salvage some sort of performance as the jet began to decelerate.

Each throttle advance brought further engine stalls and it became clear the engine would not be useable for the remainder of the flight. Once the emergency was under control, I communicated the situation to my flight lead in order to determine the most logical course of action. Our standard conventional load (SCL) produced a drag count of 125, which put me at 500 pounds above the maximum range fuel number to the primary divert in Kuwait, which was roughly 550 nautical miles from our current position. The fuel number that we referenced was based on a medium cruising altitude of 25,000 feet and would get the jet on deck with a conservative 2.0K pounds of gas vice the actual bingo which would end up with 1.5K on deck.

The fuel number, however, is calculated with two good engines but unfortunately I only had one and was therefore unable to maintain 25,000 feet. I figured the options were limited to either receiving fuel from our current tanker or diverting to Baghdad International Airport (BIAP). Given the current geo-political situation, the latest threats to aircraft assessments and the absence of Hornet maintenance support at BIAP, I concluded that the most favorable option was to receive gas from the KC-135 at my right 2 o’clock, provided I could gather the thrust required to stay in the basket.

Once the decision to stay with the tanker was made, I quickly realized that, with my energy decreasing and nearly half of my advertised thrust, I will be unable to tank at the current altitude. As I communicated my emergency to the tanker, the crew altered course, altitude and airspeed to satisfy my need for fuel.

We figured 17,000 feet would be a good starting point for a single engine tanking attempt. Once the tanker started their descent, I needed afterburner (AB) on the good motor to gain the airspeed I had lost in the decision making process.However as the tanker leveled off at 17,000 feet and slowed to 250 knots, I was able to deselect AB and give the Iron Maiden another shot. Using only the good motor to maneuver, I was able to pump up above single engine divert numbers to Kuwait and started my 500-mile trek. During the last final portion of my refuel, my lead was able to join and we coordinated a section divert to the field.

As the hurt bird, I took the administrative lead and my flight lead coordinated with air traffic control (ATC). During the next hour and a half, while we flew south toward Kuwait, I was able to get partial thrust out of the right engine allowing me to fly close to the max range profile. We coordinated with the E-2 controlling the south portion of Iraq, and they were able to get a tanker to meet us in southern Iraq. It’s now night and as we joined the compressor stalls returned at almost anything above idle making for a colorful rendezvous. My flight lead received gas since I was now well above my bingo number to the divert field and the ship was expecting her back at the boat after dropping me off.

My flight lead dropped me off and I landed uneventfully in Kuwait where the maintenance detachment discovered a bad inlet temperature probe, which caused the engine to improperly schedule fuel, resulting in multiple compressor stalls. The inlet temperature probe was replaced in a few hours and I was able to make the final recovery of the night on board the ship.

Too often, situations like this end poorly or are made harder than they need to be because of poor communication and headwork. After the initial shock of the emergency subsided and the procedures completed, the coordination and decision making between flight members and outside agencies was crucial to the successful transit and safe recovery. By breaking down this emergency into manageable parts, the flight members were able to make correct and timely decisions that ultimately resulted in the safe recovery of a single engine Hornet back to a friendly airfield.

 

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