The new chief of US Army aviation acquisition has warned that he has few options to respond to a potential round of budget cuts after more than five years of unprecedented growth.

Brig Gen Timothy Crosby told the Quad-A convention on 6 May that the branch has already received orders to run "budget drills". The drills raise options for cutting base spending for army aviation procurement and maintenance, which totaled $6.7 billion last year.

The aviation branch has also been asked to fund move its war replacement and sustainment costs out of the Pentagon's supplemental budget, which currently accounts for more than one-third of the branch's overall spending, $2.3 billion.

Moreover, recent cost-saving measures, such as multi-year procurements for the Boeing AH-64 Apache and CH-47 Chinook, mean branch officials have little room to manoeuvre if budgets are squeezed.

"Our hands are a little bit tied when they start looking [for budget cuts]," said Crosby, adding as he pointed at a budget chart, "because that one [Chinook] and that one [Apache] have multi-years. My flexibility is going to be limited."

With the Pentagon officials demanding even greater numbers of deployed unmanned aircraft systems (UAS) for surveillance needs, Crosby's options for budget cuts are likely focused on utility aircraft, such as the Sikorsky UH-60 Black Hawk and EADS North America UH-72 Lakota.

The budget pressure also raises doubts about the army's ability to support a replacement for the Bell Helicopter OH-58D Kiowa Warrior armed scout helicopter after Fiscal 2012.

Crosby told the convention audience to not be discouraged from proposing all-new aircraft to meet emerging needs despite the budget pressures. However, the potential budget squeeze comes as the army prepares to justify launching either a Joint Heavy Lift (JHL) programme or a Joint Multi-Role (JMR) programme to replace the Boeing AH-64 and UH-60.

The JHL is one of the army's options for the Joint Future Theater Lift (JFTL) requirement, which also includes USAF proposals based on fixed-wing, short takeoff and landing (STOL) concepts.

An analysis of alternatives for JFTL, which will identify the most cost-effective solution, is likely to begin late in the third quarter, said Brig Gen Walter Davis, director of the army aviation task force. Davis acknowledged that timeline makes the schedule very "tight" to support a go-ahead decision in the Fiscal 2012 budget.