Wait........the Spitfire used wooden propellers? I never knew



Internet is wonderful................


"LONDON, May 23. The Royal Commission on inventions last night announced it had awarded £.15,000 to Mr. Bruno Jablonsky for his laminated wood aeroplane propellers which helped to win the Battle of Britain.

"Mr. Jablonsky, a Polish Jew, came to Britain in 1930, and founded the firm of Jablo Propellers Ltd. He did much of his experimentation on the propeller at a laboratory at the bottom of his Croydon home's garden. Finally, he perfected a plastic wood which replaced metal propellers and enabled the Government to divert much needed metal to other purposes.

"Previously it had been found impossible to produce wooden propellers which would stand the strain of such modern high-speed aircraft as the Spitfire. 'Almost all Spitfires and Hurricanes in the Battle ot Britain were fitted with my laminated wood propeller,' Mr. Jablonsky said to-day."

So Spitfires and Hurricanes did not have controllable pitch/constant speed propellers. Fascinating. I had no idea.

The turboprop I'm most familiar with did not maintain constant torque, it maintained constant TIT. Trying to maintain constant torque at a constant prop RPM while in a climb resulted in overtemps, so the TIT became the controlled parameter.

KenV

Individual wooden blades fitted into hubs which allowed variable pitch/constant speed. And nowadays the blades tend to come from Germany...

Ken, the original Watts props fitted to the Spit and Hurricane were indeed fixed pitch props. Later props were wobbly ones, ie variable pitch

This shows the various props

http://spitfirespares.co.uk/propellors.html


I have "spoken" via email In the past with the chap that produces the pens ( nothing to do with me ) and he told me he only uses props that are fit for nothing else, ie well past the possible display standard.

Sorry for the thread drift.

..

I'm still using my Fisher pen or 5B pencil when I'm writing in my bed or on the wall board !
KISS !

Back in the air?
 

Good to see an A400M flying again today in the local area. I presume it was a Brize-based Atlas?

No further information yet on the AD&S website, but I would assume that the cause of the MSN23 accident has now been positively identified and adequate provision made to prevent anything similar happening again?

Beags:
 

Good news.

The article states "to immediate effect"- guess Beagle saw it as the release was coming of the presses...

Germany to follow in a few weeks article states. No word on other customers or those still operating with the manufacturer. Paris show next week.

So like Beagle says, must be high confidence between proper software/loading process and suspect software/process. Will be interesting to learn how that was sorted.

FWIW, a relatively new design with a similar problem?
Deadly Osprey crash spurred safety changes, heroics | SanDiegoUnionTribune.com

There's a salutary lesson about AEA integration in that article.

I say no. Sounds like the crew of the MV-22 started up and took of while in maintainence mode, robbing the engines of ~20% power- so human factors primary cause, design (allowing flight in that mode and no warning/indicators) contributory.

Reports of A400 Crash, Saville, Spain
 

Any news about the investigation? Or tagging it as military voided any reporting obligations?

Kevan Jones, MP, has formally asked the Secretary of State for Defence what outstanding safety issues there are relating to the A400m Atlas aircraft.

In his reply, Philip Dunne takes a while to say not very much, but he ends with this If you want to see more, I'm indebted to Think Defence at 4554 - Future Large Aircraft (Answered) - Think Defence
but if you want it from the horse's mouth, then Hansard is probably your best bet.

airsound

Is this still being investigated? Or just a "nothing to see here" incident?!


Well little bit more than 2 years now and seems this has just never happened

Airbus knew of software vulnerability before A400M crash

PARIS/SEVILLE (Reuters) - Airbus and European safety authorities were warned in late 2014 of a software vulnerability in the A400M military plane that was similar to a weakness that contributed to a fatal crash seven months later, Spanish investigators have found.

The Airbus-built cargo and troop carrier crashed near Seville during a test flight in May 2015, killing four of the six crew, after three out of four engines froze minutes after take-off. Data needed to run the engines had been accidentally erased when Airbus workers installed software on the ground, and pilots had no warning there was a problem until the engines failed, Reuters reported weeks after the disaster, citing several sources with knowledge of the matter.

A confidential report by Spanish military investigators into the crash, completed this summer, sheds new light on poor coordination and misjudgments that have dogged Europe’s biggest military project. The findings confirmed the engines were compromised by data being wiped, according to extracts of the report seen by Reuters and three people familiar with the inquiry.

The report also said the engine-makers had warned Airbus and the European Aviation Safety Agency (EASA) in October 2014 that software installation errors could lead to a loss of engine data, and that technicians may not receive any warning before take-off that a problem had occurred.

When contacted by Reuters, Airbus said the crash was the result of “multiple, different factors and contributory causes”, but declined detailed comment about the investigators’ findings because they are not public. The planemaker has since reviewed all systems and acted to “ensure the chain of identified causes could not happen ever again”, a spokesman added.

EASA declined to comment.

The engine-makers Europrop International (EPI), a pan-European consortium owned by Britain’s Rolls-Royce (RR.L), Germany’s MTU (MTXGn.DE) and France’s Safran (SAF.PA), declined to comment.

Spain’s defense ministry, whose air accident agency conducted the investigation, also declined to comment......

No comment all round... Not a surprise if it was known within the organisation that engine software could be wiped and no-one would know.

Not exactly an open, transparent and safety-lead investigation process is it.

Well they requalified what was in my view a civilian test flight into a military one and decided to completely burry the investigation.

Apparently there seems to be a huge case of negligence here and some people are leaking the findings.
All in all I'd say that this reflects extremely poorly on CASA / EADS.

Hmm suprised this doesn't generate more noise. It is quite a big deal in my book.
Errors happen but in this line of business avoidable mistakes are no acceptable.

Fun facts
 

Ah! The old (2^31) - 1 hundredths of a second signed 32 bit integer problem.

I first saw this in about 1997 in production kit that was expected to work for years without a reboot.

In that case the code came from some old Unix(y) stuff that was re-purposed. The thing simply stopped working after 248 days until turned off and on again.

248 days = 2,142,720,000 hundredths of a second
(2^31) -1 = 2,147,483,647

Not sure we'll ever get to see much in the way of a report.

It's well known that the aircraft suffered a dramatic loss of thrust, but probably also an accident that would have had a somewhat better outcome had they conceded a forced landing off-base was inevitable and concentrated more on a wings-level arrival while they still had limited control (i.e. enough airspeed) of the aircraft.

I think the Mars Climate Orbiter ended up costing a fair bit more overall....

https://sma.nasa.gov/docs/default-so...vrsn=eaa1ef8_4

Although it no longer directly affects me since I'm retired, shortly after the crash multiple commercial operators and the FAA came to us and wanted to know if this issue with the engine control software could possibly affect any of the Boeing commercial aircraft. I drafted up a stock response that basically said 'We can't answer that question because Airbus/EASA haven't provided sufficient information for us to understand the cause. Please come back when an accident report with the root cause is released'. Sounds like that's not going to happen - fortunately for my co-workers most people have pretty much forgotten about this one and are no longer asking the question.

I worked engine controls and FADEC software for the majority of my career. I was also an engine controls DER or the delegated equivalent of a DER for 28 years. I know a lot about engine controls and FADEC software.
If I put on my conspiracy hat for a minute, I suspect the root cause is clearly known and so embarrassing to Rolls, Airbus, and EASA that they are covering it up and it'll never be publicly released. A very basic requirement for 'modifiable' critical software is that it has to have failsafe protections incorporated. If the necessary data hasn't been loaded (or is invalid), you either prevent operation (i.e. the engine won't start, or if it starts won't go above idle), or you program default values that will allow safe (although not optimal) engine operation. Oh, and you put up a bunch of fault messages. FADEC software is level A flight critical, it's certified to the same level as FBW flight control s/w.
If I assume that the limited public information on the cause is remotely correct - basically that torque curves were not correctly loaded in the FADEC s/w on multiple engines - and the most basic protections to prevent unsafe operation were not in place - it means that NONE of the people responsible for certifying the FADEC software did their job (again, Rolls, Airbus, and EASA). Further, there was a catastrophic breakdown in Airbus QC to allow an aircraft to be released for first flight without the appropriate s/w loaded.
Approving FADEC software without the most basic of safety protections is unforgivable - those responsible should loose the jobs. IF that's what happened and it's being covered up, that's criminal - people responsible should go to jail...

For me, the really puzzling part of this accident is that the engines initially produced enough thrust to get safely airborne, and do so without any warning or caution indications, but then suddenly stopped producing enough thrust to stay airborne. That is one heck of a troubling failure mode for incorrectly loaded software. That such a failure mode was not identified and positively prevented as tdracer noted above is indeed very very disturbing. And if it is being covered up, would indeed seemingly be criminal. I'm not saying there is or has been a cover up, but everyone involved sure appear to be very tight lipped with the facts concerning this fatal accident. What assurance do the current and future operators of this aircraft have that the problem is fully understood and has been thoroughly designed out to prevent a recurrence?

No idea how the Airbus logic works, but on Boeing EICAS the takeoff inhibit doesn't kick in until 80 knots, so if there is something wrong you can do a low speed abort.
On Boeing, if the FADEC detects a serious fault, EICAS message "ENG X CONTROL" (L/R ENG CONTROL on twins) is displayed - the procedure is No Dispatch. ENG CONTROL is inhibited above 80 knots and in flight - the logic being there is not procedure once airborne, and if the engine is still running we don't want the crew to shut it down because of the message.

I am still not convinced this was not a civil flight (as far as I understand the pilots where civilians employees of Airbus and the plane was not yet handed over to it's intended customer) and the total lack public investigation report (even a somewhat censored one) is really a shame. I really hope that the heads that needed to roll did so.

Given that France, Germany, Spain and UK all released their aircraft for flight following the initial investigation, these operators must have received suitable assurances from Airbus Mil or the aircraft would have remained grounded. As an example, Boeing assured the UK that Rivet Joint was fully airworthy at point of delivery but the MAA was not convinced; the aircraft stayed on the ground (for many months) until the UK had enough information, beyond that provided by the manufacturer, to satisfy the assurance requirements of the post Haddon-Cave airworthiness environment. The fact that any assurance in this case has not been made public does not mean that none has been offered to customers.

As for whether it was a civil or military flight (question from atakacs), most nations treat the operation of aircraft designed for military purposes as being military in nature, regardless of the status of the crew, because the aircraft are not designed or built to the standards that would apply to a civilian aircraft. It would be for Spain to decide on publication of the investigation report for a military accident that happened on its turf, not Airbus.

In the US, military transports not yet delivered to the military customer (via DD250) are assigned a temporary FAA "N" registration and operated under FAA "Experimental" rules. Every KC-46 and C-17 that has flown was so registered prior to DD250. Indeed there are four KC-46 tankers and one C-17 stored here in San Antonio awaiting delivery to the military customer. Each has a temporary "N" number on the tail.

Separately, both the A400 and KC-46 are initially civilly certified. On the KC-46 many mods have a civil STC (Supplemental Type Certificate) and some mods have an MTC (Military Type Certificate.) But the basic airframe is civilly certified.

I get that. But it's one thing to say: "Your aircraft did not get the latest software load and are therefore safe to fly," and an entirely different thing to say: "Any and all new software loads we give you in the future are guaranteed not to result in a similar failure." Absent a detailed accident report, what assurances do the current and future operators have that the guarantee is worth anything?

The impressive safety record of modern aircraft is due to the incorporation of countless lessons learned from previous aircraft accidents.
To put it quite bluntly, if they never release the cause of this A400M accident, and any other aircraft crashes due to a similar problem, those responsible for not releasing the accident cause are guilty of murder.

My understanding is that the A-400 was always built as a dual use (military and civilian) aircraft, with all relevant EASA certifications.
Although this bird was (if memory serves) to be delivered to the Turkish air force it was still registered / operated by Airbus.
I guess (and hope) the families have been generously compensated and the lessons learned.