The Army chief of staff told senators "tough" choices must be made in uncertain fiscal times, and up to 46 percent of active brigade combat teams might need to be cut if full sequestration hits in 2016.Gen. Ray Odierno testified before the Senate Armed Services Committee April 8 at a hearing on the active Army and Reserve force mix related to the Defense Authorization Request for Fiscal Year 2015 and the Future Years Defense Program.Other witnesses were Gen. Frank Grass, chief of the National Guard Bureau, and Lt. Gen. Jeffrey Talley, chief of the Army Reserve and commanding general of the U.S. Army Reserve Command."We must make tough but necessary choices," Odierno said.Adding, "We must ensure we have the best Army possible, even under full sequestration."He said if full sequestration returns in Fiscal Year 2016 and beyond, the reduction of up to 46 percent of brigade combat teams, or BCTs, in the active Army would be accompanied by a cut of 22 percent of the BCTs from the National Guard.He said that would result in the Army going from a mix of 51 percent active and 49 percent reserve component, to a 54 percent reserve and 46 percent active-component mix."The Army will be the only service in which the reserve component outnumbers the active component," he said. "We believe under these fiscal constraints, it’s appropriate."Fiscal Year 2015 requestOdierno said under the current Fiscal Year 2015 budget request, the active Army will reduce from a wartime high of 570,000 to 490,000; the Army National Guard from 358,200 to 350,200; and the Army Reserve from 205,000 to 202,000 soldiers.He called the Fiscal Year 2015 budget request a "balanced and responsible way forward."Adding, "It allows the Army to reduce and reorganize forces, but incurs some risk to equipment modernization programs and readiness."Odierno said under the FY 2015 budget request, the Army will decrease its end strength through Fiscal Year 2017 to a total Army of 440,000 – 450,000 in the active Army, 335,000 in the Army National Guard, and 195,000 in the Army Reserve."This should be the absolute floor for end-strength reductions," he said."In order to execute the defense strategy, it is important to note that as we continue to lose end strength, our flexibility deteriorates as does our ability to react to a strategic surprise," he told the committee."Our assumptions about the duration and size of future conflicts, allied contributions, and the need to conduct post-conflict stability operations are optimistic. If these assumptions are wrong, our risk grows significantly," he said.Sequestration riskWith sequestration-level caps in Fiscal Year 2016 and beyond, Odierno said the Army could have to reduce its total end strength even further – to 420,000 in the active Army, 315,000 in the National Guard, and 185,000 in the Army Reserve.From the wartime highs, that end force strength reduction would be 213,000 soldiers from the total force, he said.The active Army would represent 70 percent of those reductions, compared with 20 percent from the National Guard and 10 percent from the U.S. Army Reserve.Reserve component riskGrass said the uncertain fiscal environment in the future will certainly impact the National Guard.These challenges come at a time, he said, when the country is facing "asymmetric and conventional threats from state and non-state actors."He said any cuts that would drop the guard force below the proposed 335,000 "present too high of a risk in my view, not only in terms of the threats we face overseas, but also in the homeland."Talley said Odierno’s directive for an Army Reserve end strength of 195,000 by 2017 is an "acceptable risk" to sustain a ready and operational reserve force.However, if the Army Reserve is forced to go down to 185,000, that would "negatively impact our ability to provide technical enablers, skills and capabilities vital to success in many missions," he said.Aviation restructureOdierno said an initiative to restructure the total force’s aviation will allow the Army to eliminate obsolete airframes, sustain a modernized fleet, reduce sustainment costs, and efficiently organize itself to meet operational commitments and imperatives.As part of the Aviation Restructure Initiative, the Army will inactivate and eliminate three complete combat aviation brigades from the active component and will move all of the LUH-72s from active component units to Fort Rucker, Ala., in order to train the pilots across all components, he said.The National Guard will maintain 10 aviation brigades, and the Army will move Apaches to the active component, while increasing the fleet of UH-60s by sending 111 of the most modern Black Hawk helicopters to the National Guard.The National Guard will also retain all LUH-72s and CH-47s, he said.Odierno said that as a result, the active component will be reduced by 687 aircraft, or 86 percent of the total reduction.The National Guard will be reduced by 111 aircraft, or 14 percent of the total reduction.The Aviation Restructure Initiative will result in better and more capable formations that are able to respond to contingencies at home and abroad, he said."My goal remains to sustain the National Guard and U.S. Army Reserve as an operational reserve," he said.Adding, "To accomplish this, we must take moderate reductions to overall end strength in order to invest in appropriate training and sustainment levels."