The U.S. Air National Guard on Wednesday identified its fighter pilot and the Ukrainian pilot killed when an Su-27UB Flanker-C fighter crashed during Exercise Clear Sky.
Lt. Col. Seth "Jethro" Nehring, a fighter pilot with the California Air National Guard's 194th Fighter Squadron, out of the 144th Fighter Wing, and Col. Ivan Petrenko, deputy commander of the East Air, Chief of Aviation from Ozern Air Base, Zhytomer, Ukraine, were killed in the crash, the 144th Fighter Wing said in a release.
"The incident occurred in the Khmelnytskyi region of western Ukraine, approximately 175 miles southwest of Kyiv, the capital of Ukraine," the release said.
Nehring was with Petrenko in the twin-seat Su-27 for a familiarization flight; no other aircraft were involved in the mishap, U.S. Air Forces Europe-Africa said earlier Wednesday.
The incident is under investigation.
Nehring had been a member of the 144th for more than 20 years, officials said. He began his career as an enlisted crew chief before being selected for a pilot slot, flying the F-16 Fighting Falcon for more than 15 years before converting to the F-15 Eagle, Guard officials said.
"We are a close-knit family and when a tragedy like this occurs, every member of the 144th Fighter Wing feels it," said Air Force Col. Daniel Kelly, commander of the 144th. "We share in the sorrow felt by Jethro's loved ones and our thoughts and prayers go out to his family and friends as well as those of the Ukrainian aviator."
Nehring, serving as the operations officer in the joint operations center during Clear Sky, was handpicked for the assignment because of his flight background.
"This is a sad day for the United States and Ukraine," Maj. Gen. Clay Garrison, commander of the California Air National Guard and the exercise director, said in a separate release. "Our deepest condolences go out to the family, friends and fellow airmen of both the U.S. airman and Ukrainian aviator who were killed in the incident."
Garrison, a pilot with nearly 4,000 hours in both the F-16 and F-15, spoke with Military.com last week before the crash.
"The Ukrainian air force would like to increase their ability to operate with the regional partners," he said in a telephone interview. "Their country's at war, and the[ir] air force is an important part of [their] capabilities."
Garrison explained that due to their geographic location -- next door to Russia, but also close to NATO allies -- "they would like to do more, and be a better regional partner."
He continued, "NATO is the gold standard of military defense agreements, and the way we train is very useful."
The general said the purpose of the entire exercise was to inform and equip the Ukrainian air force with similar training techniques so they too would understand the practices and procedures NATO partner nations adhere to when they fly.
The last time the Air Force participated so extensively in a Ukrainian exercise was in 2011 during Exercise Safe Skies, focused on air-sovereignty rules of engagement, Garrison said.
Meanwhile, Clear Sky -- which marks the 25th anniversary of the longstanding State Partnership Program between the California Guard and Ukraine -- is intended to become a stepping stone to understanding higher task flight operations. Once the U.S. leaves, Ukraine could integrate with the Romanians, Poles or whichever partner would be willing to practice as needed to keep up with their slow but steady military flight achievements, Garrison said.
This time around, the Ukrainians would not be learning how to advance against Russia in the electronic warfare domain or the realm of hybrid threats, nor would they be flying in ways designed to circumvent or evade surface-to-air threats to include bomb-laden drones.
Electronic warfare is a popular method being used in Eastern Ukraine. For months, Russian-backed separatists have been using jamming technology to misdirect or take out the commercial drones Ukrainian soldiers use to conduct aerial surveillance. The move, first observed in 2014, put U.S. troops on alert as they trained Ukrainian guardsmen on the western side of the country. There's also an offensive front: Russian drones carrying grenades or other types of ammunition have thwarted Ukrainian air space or have taken out facilities in country.
"We've [first] got to establish a common language and common set of rules [with] which we can operate," Garrison said. "This will set us up as we go further; but the Ukrainians are interested in getting there."
He continued, "[But] the Ukrainian ground base defense forces are participating as well, so as we progress with each training sortie...there's going to be some integration of forces that includes [surface-to-air] threat reactions."
U.S. assets participating in the exercise at Ukraine's Starokostiantyiv Air Base included six F-15C Eagles from the 144th Fighter Wing; an F-15D from the 48th Fighter Wing, based at RAF Lakenheath, England; and C-130Js from the Guard's 146th Airlift Wing, operating out of Vinnytsia Air Base roughly 80 miles away.
Clear Sky is the first time F-15s from the California Air National Guard have touched down in Ukraine, and the first time the aircraft has been in Ukraine overall since 1998, Garrison said.
Pararescue airmen from California's 129th Rescue Wing have also been in Vinnytsia for combat search-and-rescue training with their Ukrainian counterparts, including some Ukrainian helicopters. Other U.S. airmen and aircraft such as an MQ-9 Reaper drone have been operating out of Poland for the missions. Some refueling aircraft, operating out of Powidz, have also participated.
Guardsmen in intelligence ops and air weapons control from Pennsylvania, Ohio, New York, Alaska and Washington, and some active-duty airmen from bases in Europe, have also been involved.
On the Ukrainian side, Su-27 Flankers, Su-25 Grachs, Su-24 Fencers and MiG 29 Fulcrums have been participating out of Starokostiantyiv. An Antonov An-26 twin-engined turboprop civilian and military transport aircraft has also been used in aeromedical evacuation training.
Joint terminal attack controllers from various countries including the U.S. were working about an hour north of Starokostiantyiv to call in strikes for the MQ-9 from the 163rd Attack wing operating out of Miroslawiec Air Base in Poland, Garrison said.
Poland also participated in the JTAC operations with its F-16s, as well as air-to-air simulated runs with Ukrainian fighter jets, he said.
The Su-25s were being used primarily for close air support during the same drills. The tactical airlift C-130s and An-26 together were trying out low-level flight training, airdrops and assault landing to "share tactics, techniques and procedures," Garrison said.
Last but not least, cyber defenses have been in play: California Guardsmen from the 195th Wing out of Beale, as well as Guardsmen from the 175th Wing in Warfield Base, Maryland, have been helping the Ukrainians to understand basic "network management, instruction ... and tools to ensure that your network is properly defended ... and connected," he said.
In all, the multinational exercise has involved approximately 950 personnel from nine nations, including Belgium, Denmark, Estonia, the Netherlands, Poland, Romania, Ukraine, the United Kingdom, and the U.S.
The hope is, "when we come back, we'll be able to start where we left off so the training scenarios will be more complex," Garrison said. "We've introduced the process that allows us to train together, so next time ... we're going to start to add on. That's the ultimate goal."
-- Oriana Pawlyk can be reached at email@example.com. Follow her on Twitter at @oriana0214.