The jobs of up to 1,500 public servants in the Defence Department are on the chopping block.

The “First Principles Review” into Australia’s Defence establishment has called for 1,000 to 1,500 officials to lose their jobs by the end of 2016.

The review will be looked-over by the National Security Committee next week, but the Defence Department is already preparing to implement its 67 recommendations from August 1.

The long-awaited review is currently only being circulated among Defence senior management.

Defence staff will be nervously awaiting publication of two other reviews; The Force Structures Review, and the Defence White Paper which were due this month too.

Civilian staff at Defence HQ believe the Force Structures Review will call for an increase in the 57,000-strong Australian Defence Force.

It is expected that more civilian scientists and technicians will recruited into the armed forces’ public service.

It remains unclear how the Federal Government will meet the two conflicting goals.

The latest Defence Department cuts come after 3,000 full-time equivalent employees were offloaded through natural attrition and redundancies.

Defence now employs about 19,300 people.

Technician and engineering workers union Professionals Australia has warned that the haemorrhaging of skilled engineers and scientists from Defence has reached a crisis point.

“On Monday the secretary said in relation to skills and expertise challenges that Defence is like a Dalmation,” union official Dave Smith told Fairfax Media.

“It's more like Swiss cheese.

“There is a thin grey line of engineering and science expertise across the agency.

“We are exposed in too many areas.

“Successive cuts to this workforce have created dangerous capacity gaps that risk both national security and operational safety.

Mr Smith says even with all the cuts, there are vital jobs sitting empty.

“The 2014 DMO engineering workforce audit identified that the current vacancy rate places further strain on critical positions and may pose a risk to Defence operations,” he said.

“We have warned the agency about these safety risks and their responsibility under work health safety legislation.

The union wants Defence management to rally against the cuts.

“Proposing further cuts to the Australian Public Service workforce is irresponsible,” Mr Smith said.

“[Defence Minister Kevin Andrews] needs to step in and step up.

“David Johnston wasn't up to it.

“You can't be serious about national security and defence capability if you not only don't fix critical skills gaps but make them considerably worse.”