This one isn't strictly (or remotely) an engineering scare but it is a spooky scare that relates to Halloween.

For years my wife and I threw a family Halloween party on the Saturday nearest Halloween, 30+ people in our 2 bedroom cottage - a bit cramped. A few years ago the party was done and dusted and my parents were paying us a visit on the Sunday after the party. We were prepping for the visit when we got a call from our neighbour. He periodically lived in Bulgaria with his partner (now wife) and hadn't been able to get in touch with his father for a few days, he asked if we could pop next door and see if the old boy was ok.

His father was approaching his 90th birthday at this point, so the concern for his well-being was reasonable. A large amount of looking thru windows and knocking at the door elicited no response, the key was in the lock on the inside for the only access we had so we couldn't get in.

I decided I needed to get to the upstairs windows and take a look in the old boy's gym - yup, an 89 year old still worked out (static bike and the like). Up the ladder I went and onto the extension roof, on looking thru the window I spotted him having fallen over on the bike. He was pressed up against the wall and - from the colour of him - very dead.

The rest involved the police, ambulance and all the usual authorities - just as you'd expect - plus a rather sobering conversation with his son.

So that's my 'scare', finding a dead friend on October 31st - like I said, it isn't engineering, but every Halloween I think of him, my own personal dead body that wasn't a prop but the real thing, and he'd been right there throughout our party.

Eric, I salute you you crazy old man!

I'm not involved in twitter ... thankfully.

I guess this one falls into the engineering world of self inflicted.

Many years ago when NZ had only 960 channels up and down the country, we were responsible for the maintenance of these Microwave links.

We received an alarm for the loss of one channel at a remote site some 80 miles up north.

Myself and a newer staff member were sent for a "push the button" trip, and in the typical boy scout tradition I made sure the trainee had his jacket (despite it being a hot north westerly of 25+ degrees).

We duly arrived at the site a few hours later, and sure enough one channel appeared dead, or at least not working as expected.

Resets and the like didn't fix it, which had a few heads back at work being scratched feverously.

There was doubt cast upon the detection systems so a switch to that channel was authorised (knowing that it would drop all traffic), and sure enough it proved that it wasn't working.

By now several hours had passed, the temperature had dropped, and it was dark.

Several more hours with various phone calls and it was established that someone had switched on a new system further up the link, and it was interfering with this channel.

They hadn't told anyone or sought permission to turn it on, and since this equipment wasn't meant to be running, no-one considered that as the cause.

Hence the self inflicted bit.....

Several more hours and someone made it to the other site and turned it OFF.

Eventually we got home at 2am, and needless to say the trainee never ever went anywhere without a jacket again.

You also have to put this into the context of the 1980's.

Cellphones hadn't made it to NZ, and if they did there was no coverage in those areas anyway.

The VHF service we had, didn't extend in that direction due to hills, and local topography, so it wasn't until the techs that switched it on returned to home base, that someone put two and two together.

In this instance no-one got hurt, and apart from some embarrassment and loss of redundancy, we got away with a valuable lesson.

The trainee learned to prepare for the worst, and we had the next day off.

Mark

I remember well, the time I left of vacation after checking out the software before an acceptance test.  Everything look fine, so I departed feeling confident that it would pass.

Fast forward two weeks and I return to the office to have a large number of people waiting outside my office wanting to know why MY software failed the test.

So I said, "everything worked fine when I left, what did you do before the test?"  The answer was "Nothing, we just fixed the hardware."

So I said, "What do you mean, you just fixed the hardware?"  The answer was, "We just made it comply with the specifications."

After doing some preliminary testing, I discovered that the "fix" involved removing noise on the servo lines running into the DUT.

I had programmed the DUT to do a little filtering of the usually noisy servo lines so that it did not initiate calculations for just noise.

The solution was a bit strange.  To make the DUT respond to the now clean servo data, I made a little function that would "add" noise to the servo outputs for the device we were running the acceptance test on.

A little testing showed that my fix worked fine and the device was not ready and indeed did pass acceptance test.

Lesson learned, never leave the hardware guys alone when you are writing embedded software.  They sometimes think a simple hardware fix is fine, but they should always run it past the systems or software engineer to see if it affects any of the code.

DAB

The image that the-dubster was trying (and failing) to insert, done from my non-admin user.

Been there... Done that... Barely survived!

Learning can be scary

I tend to erase traumatic experiences from my memory, but horror stories that happened to other people - no problem. Anyway this one happened to me: I was working on load cells on a vehicle test stand which measured forces required to break seat belts and seats. The system ran on hydraulics at 1750 psi. The hydraulic pistons in the picture could exert over 5,000 pounds of force. The 30 liter system accumulator was mounted behind the lower I-beam that the actuators were mounted to. The yellow belts were used to test the system before destroying a car. I was well aware of the energy in the system and the violence it was capable of, but there were lots of safety systems.

I was working on the cables on the pistons, when the fitting on the end of the accumulator popped off. Fortunately the fitting stayed attached to the hose but the oil in the accumulator shot out like a steel bar and hit the control room 40 feet to the left. Maximum pressure in a fire hose is about 290 psi, so you can imagine oil coming out a 1 inch nozzle at 1700 psi. Gravity had no time to act - the oil hit the wall at the same height as the accumulator. I dutifully trotted off the platform to a safe distance. When I say trotted I mean I could give lessons to the Flash in how to move quickly. If the other end of the hose had let go I would have been in much more serious trouble, possibly receiving a highly toxic oil transfusion. When the oil hit the wall it sprayed high in the air and covered the whole area with oil rain. Some of the ceiling tiles in the control room had been removed to improve air circulation, so several racks of equipment in there got coated with oil. Pretty tough to pass off the incident as "we spilled a little oil". We did alter our safety precautions after the incident. Sometimes it is fun to learn, sometimes it is just imperative.

I don't use twitter (and this wouldn't fit anyways) - no 'featuring of story' with #sharethescare then but I'm telling it anyway . . .

I'm not sure if this counts, but here it goes.

It was a rather uneventful day at work, running ANOTHER functional check on the Panavia Tornado F3 (ADV) fast jet radar, and it was all going fine. The radar pack was sat behind the radome and the only way you could open this was by the radar being in it's 'parked' position. When running, the radar scanner/antenna arc swings right thru where the radome opening arc goes. Still with me?

To avoid collisions, the radome, when opened, is held back with a 'banana' stay - handily clipped beneath the scanner when not in use.

The main radar pack now sits in ANOTHER openable part of the front of the aircraft - the 'maxi skirt', opening THIS brings the open radome right back alongside the fuselage - pointing rearwards. This bit is held open by a rather chunky catch that 'breaks' in the middle and folds in half to close.

And now, to the crux of the story, we were running functs, the scanner/antenna assembly was sweeping back and forth - 270 bar of hydraulics moving it quite well thank you, and the Airframes guys asked us to close the maxi skirt so they could get the aircraft staging down that side of the jet.

Dutifully I grabbed the maxi skirt catch and unlocked it, and my 'oppo' copped for the radome and started swinging the thing shut.

What we (I) didn't realise is my 'oppo' had not bothered to install the radome stay (when both radome and skirt are open the whole lot naturally swings all the way open due to the weight).

I now know what it sounds like when you push a radome into a moving radar scanner/antenna array (only the radome closed, not the skirt where I was).

I also know how much damage that causes to the £186,000 (+ vat) 'Folded Focus Cassegrain Antenna'.

(This is the open radome (no stay fitted I see), the maxi skirt release is ringed yellow, the opening of the skirt (badly) marked with red wiggly line).

No I don't have pictures of how that lovely 'chicken wire and fibreglass' antenna looked afterwards - you can probably guess.

Just for the heck of it, the edited image is in this post about not being able to attach the image here!!!!

(Well, I've inserted the image 12 times now but I get told to 'poke off' . . . . . . NVM!

Have a link to an 'unedited' picture instead . . . . . skirt handle can just be seen above black writing 'down and to the left' of the yellow labels - skirt opens just in front of that!

I once went through ISO 9001 training.  I almost fell asleep, never to wake again... bwaa hah hah ha ha.

Does that count?  It was truly a nightmare