A US Air Force officer with an “exemplary service record” may be sent back to America and discharged after he was caught driving a motorbike in Alice Springs just weeks after the court disqualified his driver’s licence.

Pacific Command Sergeant Carlos Alberto Novelo was convicted and fined $1700 in Alice Springs Local Court for driving a motor vehicle while disqualified on Friday. He was also disqualified from driving for a further six months.

The court heard Sgt Novelo was driving a red Honda 125cc when police pulled him over for a random breath test on Barret Drive at 11am on Friday May 27.

He did not return a blood alcohol reading.

He was on his way to deliver a seminar on suicide prevention in the defence force at Commander Major Troy Ruby’s house, according to defence lawyer Murray Preston.

“What has occurred has really put his career at risk,” he said.

“He has spoken to his immediate superiors and it has gone all the way to the top.”

“It affects his whole standing with the Air Force.”

“I would ask your honour to take a course that reflects his excellent behaviour and service out here assisting the Australian people and the American Government.”

Sgt Novelo, 33, has been in the US Air Force since he was 19 years old.

“The Air Force does impose whatever penalties they deem appropriate, which could see him sent back to America and possibly discharged,” Mr Preston said.

The maximum penalty for driving while disqualified is 12 months in prison.

Several thousand demonstrators formed a human chain along the perimeter of a U.S. Air Force Base in southwest Germany on Saturday in protest against drone operations by the United States.

Several thousand demonstrators formed a human chain along the perimeter of a U.S. Air Force Base in southwest Germany on Saturday in protest against drone operations by the United States.

The demonstration was organized by the alliance "Stop Ramstein - No Drone War", which says the Ramstein base transmits information between operators in the United States and unmanned drone aircraft in places such as Iraq, Afghanistan, Pakistan, Yemen and Syria.

Police estimated 3-4,000 people had formed the chain close to the base, which serves as the headquarters for the U.S. Air Forces in Europe. Organizers spoke of 5-7,000 people. No comment was available on Saturday from officials at Ramstein.

The use of drones is highly controversial in Germany, where an aversion to military conflict has prevailed since World War Two. Organizers say allowing data for drone deployments to be routed through Ramstein goes against the German constitution and want the base's satellite relay station to be closed.

Nearly 15 years after a drone first fired missiles in combat, the U.S. military program has expanded to become an everyday part of the war machine for carrying out surveillance and launching strikes.

Critics say drones often miss their intended targets, can only partly relay what is happening on the ground and encourage warfare with impunity, waged by people at computer screens far from danger.

President Barack Obama last month approved a drone strike in a remote area of Pakistan that killed Taliban leader Mullah Akhtar Mansour. U.S. officials said he had been overseeing plans for new attacks on U.S. targets in Kabul.

The U.S. and Australia have pushed back plans for the deployment of a 2,500-strong Marine Air Ground Task Force to Australia's Northern Territory until 2020 as they nail down the final details, including cost-sharing, Australian officials say.

The Marine Corps started building its presence in the port of Darwin in 2012 and grew its rotational force, which spends six months of the year training there, to just under 1,200 troops by 2014.

However, the growth of the force, which was to have included the task force within five years, has stalled with U.S. and Australian officials reporting only 1,250 Marines there this summer.

Australian Defence Force officials said in an email that they would work toward rotations of 2,500 Marines and equipment to Darwin by around 2020.

Australian national security consultant Ross Babbage said the two countries have been negotiating for three years over who would pay costs associated with the rotational force.

"There is no space on RAAF Darwin and Robertson Barracks (the facilities where Marines stay in Darwin) to facilitate that kind of growth (up to 2,500 Marines)"

A B-52 bomber has crashed shortly after take-off at a US base in Guam, the US Air Force says.

It says all seven crew members safely left the aircraft after the incident at 08:30 local time (22:30 GMT Wednesday) at Andersen Air Force Base.

Images on social media showed plumes of smoke rising from the wreckage.

The bomber was deployed to the US island territory from North Dakota as part of the military's continuous presence in the Pacific.

Local news site Kuam quoted the Guam governor's office as saying: "We assure the public this does not appear to be an attack."

the Air Force says steps are being taken to minimise the environmental impact, without providing further details.

A United States Air Force B-52 Stratofortress long-range strategic bomber will conduct training activities in the Northern Territory and operate out of RAAF Base Darwin throughout next week.

A Defence spokesman said United States Air Force training in Australia continued a long-standing and mutually beneficial program of combined training activities and exercises.

Exact flight dates are not being released for security reasons.