Embarrassing German military hiccups in sending weapons to Kurdish fighters in northern Iraq have proven a "reality check" for Berlin which is seeking a bigger role in international crises, analysts said Monday.

Days-long delays in sending German arms and training personnel to Peshmerga Kurdish fighters battling Islamic State jihadists due to aircraft problems have coincided with revelations about wider deficiences in defence hardware.

News website Spiegel Online published figures, which it sourced to the Bundeswehr armed forces, indicating that just 41 out of 190 helicopters were fit for service and painted a similar picture for fighter planes.

Germany's Ebola aid mission also ran into difficulty Monday with one of two Transall C-160 airplanes carrying aid to Senegal stuck on the Spanish island of Gran Canaria due to a defect, a defence ministry spokesman said.

Defence Minister Ursula von der Leyen acknowledged in a newspaper interview published Sunday that Germany's military could not currently live up to all its NATO commitments because of equipment problems.

Germany could meet its pledges in ongoing operations and responding to crises in the short-term, she told Bild am Sonntag.

"But with the airborne systems we are, at the moment, below the target figures announced a year ago on what we want to put at the disposal of NATO within 180 days in the case of an emergency," she added.

Chancellor Angela Merkel said Monday she fully supported von der Leyen in trying to overcome the Bundeswehr's problems and creating more transparency.

"The demand on the military has in recent years ... greatly increased," she told reporters.

- 'Disaster' -

But security expert Joachim Krause, of Kiel University's Institute for Security Policy, said Germany's armaments situation was "a disaster".

He told AFP that Finance Minister Wolfgang Schaeuble had for years "condemned the Bundeswehr to not growing any more", while defence ministers have failed to define a "strategic direction".

With Germany ruling itself out of US-led airstrikes against IS jihadist targets, the government faced questions Monday about whether Europe's top economy should leave all the heavy lifting to others, and even whether it has the military capacity to step up.

"We ought really to feel uneasy," former Bundeswehr chief of staff Harald Kujat told Monday's Bild daily.

"Our allies are flying missions against IS, are therefore in action for our collective security, and we're not there.

"Europe's biggest economy and one of the most important NATO countries cannot actually act in such a way," he added.

Foreign ministry spokesman Martin Schaefer rejected as "nonsense" the notion that Germany's commitment to the anti-IS alliance should be gauged solely on whether it takes part in airstrikes.

"We respect all those who participate in these airstrikes," he told reporters. "But we have also received a lot of respect and recognition for what Germany is ready to do."

- 'All talk, no action' -

Berlin made a watershed decision last month to send arms to Iraqi Kurds.

For decades after World War II, Germany, burdened by guilt over Nazi terror and aggression, stepped lightly on the world stage and refrained from sending troops abroad.

It has since deployed peacekeepers to global hotspots, from the Balkans to Afghanistan, but has also earned criticism for staying out of other conflicts, especially the 2011 NATO intervention in Libya.

Von der Leyen, as well as Foreign Minister Frank-Walter Steinmeier and President Joachim Gauck, has this year called for Germany to take more responsibility in international crises, with arms if necessary.

Steinmeier on Saturday at the UN General Assembly reiterated Germany's willingness to take responsibility both in and with the United Nations to help relieve the suffering of people in global hotspots.

Krause said he found German leaders' ambitions for more engagement "very laudable" but indicated the country did not have the wherewithal even though it has "one of the biggest European armed forces".

He added that "it's not only embarassing, it's negligent."

The Frankfurter Allgemeine Zeitung said it wasn't enough if only Washington stepped up when Europe is at the forefront of dealing with the impact of the IS group, with refugees and jihadists returning home.

"So greetings allies! We're watching you and meanwhile talking about how we're assuming more responsibility in the world," the newspaper said dryly.

Bild said the revelations about deficiencies in military planes and hardware had been a "reality check".

"In the schoolyard one would say of the German announcement policy, all talk, no action."