The only question which matters is whether the aircraft was military or civil registered. If civil, an Annex 13 investigation is a given and report publication would follow. If military, the Spanish military process would be followed and, on previous experience, publication unlikely. I don't know the answer on registration but I'm willing to guess.

EAP

Why would the Spanish military be involved in this accident at all? The Spanish military has no design or engineering authority for this aircraft. It was never signed over to them so they don't have operating authority for this aircraft. No Spanish military personnel were at the controls, so there was not even peripheral Spanish military involvement in the flight. So why no Annex 13 investigation report?

The EASA Type certificate is here: EASA TYPE - CERTIFICATE DATA SHEET No. EASA.A.169 for AIRBUS A400M

Plausible explanations? Kind of my point, no? The point of an investigation is to positively determine cause, not "what is plausible." And the point of a report afterward is to assure all current and future operators that the cause is known and that the fix is certain. Its' damn tough to operate a fleet of aircraft based on "what's plausible." Especially when those aircraft may have to go into combat.

Further to what Ken wrote, pretty much every new aircraft - civil or military - has FADEC engine controls. The only way to prevent a future occurrence on another aircraft - civilian or military - is to publish a report pointing to root cause, so they everyone can make sure they don't make the same mistake - not just Airbus.
Like I said before, if the cause is known but not made public, and another aircraft crashes for the same cause - it's murder (manslaughter in US parlance).

​​​​​​The aircraft wasn't being developed by Airbus as a standalone PV project, rather it was developed in response to a contract agreed with OCCAR (with Spain as one of the end customers), and the contract would detail the qual and cert procedures to be followed. NB the procedures used to be available on OCCAR'S website but I can't find them. The procedures could have agreed to use Airbus' standard EASA civil approval to fly development aircraft or they could've opted to flight certification under Sp military processes (which could also rely on the civil Type Certification of the Design issued by EASA although this may not have been available for early development flying). Whichever organisation was regulating the development flying would determine which accident investigation procedures to be adopted, hence my point about the registration number, military or civil.

Complex multinational military aircraft procurement programmes tend to breed complex qual and cert procedures. A friend was a senior airworthiness person in Airbus and in the early days of A400M he said that Airbus would cover the whole project under civil processes, none of these silly military processes. I patted him on the shoulder and suggested he tell me that in 10 years time and we'd see whose vision of the future was correct.

EAP

A minor quibble, that's the TCDS not the TC but it does refer to the TC. I wonder whether a civil operator could procure an A400 against this TC in isolation as I suspect some additional military kit might be needed to create a flyable aircraft (radios?). I don't suppose Airbus would have any difficulty supplementing the TC to make it workable in a true civil context.

EAP

EAP - I think that it is potentially possible to buy a A400 for civil use only, however I imagine it wouldn't be allowed by OCCAR for some time. Obviously the mil spec kit would have to be replaced for civ and I guess the biggest impact will be in the avionics.

It was certified as a civil aircraft first before clearance of military specific roles and equipment. Possibly, the test aircraft had mil kit to make the MEL such as radios and transponder under exemption if necessary, rather than civil only equipment to be replaced by the customer specific equipment later on.

I just did some structures calcs on the wing so am not in the actual knowledge here...just what was talked about in the office at the time.

Just as a point of reference EC-001 to EC-999 is, as far as I understand, civilian registry for Spain under "Test and delivery". The registrant is listed "Airbus Military", which was dissolved in 2014 to become Airbus Defence and Space SAS (so It's a bit unclear how it could still be used in 2015). As far as I can tell no military personal works there and the people on board were civilians. As mentioned in a previous posts the Spanish AF was not in any shape of form concerned.
I guess there is no point insisting there - although there would be many objective reasons to have an Annex 13 investigation it will not happen.

I have no particular knowledge on the Airbus specifics but businesses often contract under a name of the legal entity which is quite different to the name used for business organisation or marketing. The latter names can change quite often but businesses hate the costs and complications of changing the name of the legal entity.

Edit. Is it possible that due to the OCCAR contract, EASA regard the A400M as a State Aircraft which isn't subject to Annex 13? Just a thought...

EAP

Regardless of the registry (civil, military, state, whatever) what is the reason the investigation is being done in secret and the resulting report not published? It makes no sense unless someone is trying to hide something nefarious, or someone is trying to protect someone who is guilty of at best malfeasance and at worst of murder.

The truly amazing part? They seem to be getting away with it.

Can I ask a ignorant question ,
why does no (that i know of) transport aircaft have no ejection seats?
we are constantly being told the years of training and expense of getting a pilot to a good standard is the most important thing on a aircraft(rightly so).
But yet no transport aircraft have them, fighters,bombers and trainers its a standard.I can understand if you have a full load of troops and its crashing it might not be looked on with favour if the crew eject, and the troops perish but if it's just equipment surely it's better for the crew to get out?

An absolutely safe aircraft does not exist and, for good engineering reasons, aircraft are designed to be safe enough (roughly 1 in a million per fh likelihood of fatality). Transport aircraft are generally safe enough without ejection systems whereas most fast jets need ejection systems to make them safe enough. Note that 'safety' in this context is purely associated with the risk to life.

EAP

I believe it's the case that the investigation is not open because there is no overriding mandate for it to be otherwise. ICAO aircraft accidents fall under Annex 13 and most Airworthiness Authorities extend the principle to all civil types. Investigations of State Aircraft accidents require the relevant government to make a positive decision about openness. It could be argued that there's an ethical or moral imperative to publish, and while I would agree with this, it isn't a mandate. There may be legitimate sensitivities involved rather than something nefarious. FWIW I have no idea why there is secrecy in this case.

EAP

Post #188 refers.

Some of the questions asked here in September 2018 have actually been answered in the full version of the Reuters report partially quoted in Post #296 in November 2017 ("Airbus knew of software vulnerability before A400M crash")

According to Reuters, there is a report, and they saw an extract of it. I'd guess that current and future operators will get access to the report, while you and me don't.

That's only the first step of the process. Based on the civil certification alone, the A400M isn't even allowed to carry any cargo or passengers. Actually, according to the Reuters report, one of the reasons for the accident was that Airbus and the engine manufacturer didn't agree on whether the engines were to be treated by civil or military standards.

The Spanish Dirección General de Armamento y Material (DGAM), a military authority, is responsible for the quality control at the final assembly line and issues export certificates, based on which the aircraft obtain their Airworthiness Certificates.

According to the Reuters report, Spanish officials say the A400M assembly line is a defense facility and not subject to civil rules.