Test Equipment Anonymous (TEA) group therapy thread

[Robert763]

Mildenhall Osprey on a training exercise practised landing yesterday at Cambridge Addenbrookes Helipad and on take off the wash from its twin rotors destroyed the helipad  , something that our Heli-Med copters don't do 

https://www.cambridge-news.co.uk/news/cambridge-news/addenbrookes-hospital-helipad-damage-helicopter-20444102

Huh?!? Carnage...? It's a temp helipad that doesn't appear was ever properly anchored. Am I missing something here?

Isn't that something USAF flight engineers should know better than to try and take off with that from a temp heli landing site? Or is this hospital actually using that as a permanent helipad?

No matter who's at fault... clearly a failure in the command structure and communications channels.

mnem
"Hold into your butts..."

It is (was) a permanent helicopter landing site. It was not designed for a V22. Note the matting that was lifted is NOT what the V22  landed on or that the normal helicopters land on. They land on the grass. The matting is (was) for the transfer land ambulances to stop them getting bogged down.

[med6753]

Mildenhall Osprey on a training exercise practised landing yesterday at Cambridge Addenbrookes Helipad and on take off the wash from its twin rotors destroyed the helipad  , something that our Heli-Med copters don't do 

https://www.cambridge-news.co.uk/news/cambridge-news/addenbrookes-hospital-helipad-damage-helicopter-20444102

Huh?!? Carnage...? It's a temp helipad that doesn't appear was ever properly anchored. Am I missing something here?

Isn't that something USAF flight engineers should know better than to try and take off with that from a temp heli landing site? Or is this hospital actually using that as a permanent helipad?

No matter who's at fault... clearly a failure in the command structure and communications channels.

mnem
"Hold into your butts..."

It is (was) a permanent helicopter landing site. It was not designed for a V22. Note the matting that was lifted is NOT what the V22  landed on or that the normal helicopters land on. They land on the grass. The matting is (was) for the transfer land ambulances to stop them getting bogged down.

Regardless, that stupid "matting" should have been permanent blacktop, concrete, or ashphalt. Is that hospital that cheap?   

[bd139]

Hospital is one of the best and well funded ones on the planet.

Linked to Cambridge university and been around for over 250 years.

[Robert763]

Mildenhall Osprey on a training exercise practised landing yesterday at Cambridge Addenbrookes Helipad and on take off the wash from its twin rotors destroyed the helipad  , something that our Heli-Med copters don't do 

Huh?!? Carnage...? It's a temp helipad that doesn't appear was ever properly anchored. Am I missing something here?

Isn't that something USAF flight engineers should know better than to try and take off with that from a temp heli landing site? Or is this hospital actually using that as a permanent helipad?

No matter who's at fault... clearly a failure in the command structure and communications channels.

mnem
"Hold into your butts..."

It is (was) a permanent helicopter landing site. It was not designed for a V22. Note the matting that was lifted is NOT what the V22  landed on or that the normal helicopters land on. They land on the grass. The matting is (was) for the transfer land ambulances to stop them getting bogged down.

Regardless, that stupid "matting" should have been permanent blacktop, concrete, or ashphalt. Is that hospital that cheap? 

The helipad was fit for purpose. That purpose did not include landing a V22. The problem is that the site was not properly assesed by the V22 operator before landing a completly diferent class (vectored thrust) and weight of aircraft on it.

[Cerebus]

Mildenhall Osprey on a training exercise practised landing yesterday at Cambridge Addenbrookes Helipad and on take off the wash from its twin rotors destroyed the helipad  , something that our Heli-Med copters don't do 

https://www.cambridge-news.co.uk/news/cambridge-news/addenbrookes-hospital-helipad-damage-helicopter-20444102

Huh?!? Carnage...? It's a temp helipad that doesn't appear was ever properly anchored. Am I missing something here?

Isn't that something USAF flight engineers should know better than to try and take off with that from a temp heli landing site? Or is this hospital actually using that as a permanent helipad?

No matter who's at fault... clearly a failure in the command structure and communications channels.

mnem
"Hold into your butts..."

It is (was) a permanent helicopter landing site. It was not designed for a V22. Note the matting that was lifted is NOT what the V22  landed on or that the normal helicopters land on. They land on the grass. The matting is (was) for the transfer land ambulances to stop them getting bogged down.

Regardless, that stupid "matting" should have been permanent blacktop, concrete, or ashphalt. Is that hospital that cheap? 

My dear boy all the air ambulances in the country are paid for by charity, there are no government funds of any sort made available. So, that helipad is paid for by whatever charity runs the local air ambulance service. And the field it's in is probably the property of someone else who lets them use it gratis. So no-one's being 'cheap', it's more likely that they are begging for every penny just to keep the service running. It may even be that a moveable landing setup is logistically preferable to permanent hard-standing.

[med6753]

That's right, I forget. It doesn't snow in London. The first time it snowed here that mat would be ripped to shreds when plowed.   

[Specmaster]

Mildenhall Osprey on a training exercise practised landing yesterday at Cambridge Addenbrookes Helipad and on take off the wash from its twin rotors destroyed the helipad  , something that our Heli-Med copters don't do 

https://www.cambridge-news.co.uk/news/cambridge-news/addenbrookes-hospital-helipad-damage-helicopter-20444102

Huh?!? Carnage...? It's a temp helipad that doesn't appear was ever properly anchored. Am I missing something here?

Isn't that something USAF flight engineers should know better than to try and take off with that from a temp heli landing site? Or is this hospital actually using that as a permanent helipad?

No matter who's at fault... clearly a failure in the command structure and communications channels.

mnem
"Hold into your butts..."

It is (was) a permanent helicopter landing site. It was not designed for a V22. Note the matting that was lifted is NOT what the V22  landed on or that the normal helicopters land on. They land on the grass. The matting is (was) for the transfer land ambulances to stop them getting bogged down.

Regardless, that stupid "matting" should have been permanent blacktop, concrete, or ashphalt. Is that hospital that cheap?   

Actually I think that the pad might well be a temporary one as the hospital is undergoing massive building works as can be seen in the attached pictures, the helipad is some distance and a road away from the main complex, so an ambulance would be required to transport the patient from there to the hospital. As Robert said, that is the matting / decking for the ambulance and stretchers. The helicopter lands on the grass, surrounding the matting (red square). Contrast that to the hospital just a couple of miles north of me which has a dedicated pad on top of the hospital and in the height of the pandemic we were able to see from our house, Chinnocks landing on it and transferring patients and supplies to the hospital.

I remember a few years ago visiting on summers evening, a small seaside place near us, called Maldon, which is known locally as Maldon on the mud, and we were just in time to witness the arrival of a Sea King helicopter winching a man out of the mud where he had tried to wade from his moored boat to the promenade and became stuck up to his waist in mud. After winching him out, it transferred him to a waiting ambulance behind us. As it lifted again to return to its base, the wash nearly blew us of our feet, and we were a reasonable distance away from it.

[med6753]

"Let's see what else we can destroy to piss off the Brits" 


 

[bd139]

You already destroyed our televisions with your crap 

[Cerebus]

And nicked all our actors to make it. 

[Specmaster]

"Let's see what else we can destroy to piss off the Brits" 


 

What about operation "Sky Shield" when 7 out of 8 RAF Vulcans (playing the part of Russians) attacking various targets in the USA managed to fly from their base weaving around the radar zones reaching their designated targets, which would have resulted in the total destruction of the cities, and flew back to their bases completely undetected, I bet that pissed off the Yanks 

[mnementh]

   "Let's see what else we can destroy to piss off the Brits" 

You already destroyed our televisions with your crap 

And nicked all our actors to make it. 

        BWAHAHAHAHAHA!!!

mnem
 

[med6753]

"Let's see what else we can destroy to piss off the Brits" 


 

What about operation "Sky Shield" when 7 out of 8 RAF Vulcans (playing the part of Russians) attacking various targets in the USA managed to fly from their base weaving around the radar zones reaching their designated targets, which would have resulted in the total destruction of the cities, and flew back to their bases completely undetected, I bet that pissed off the Yanks 

Yea, I heard about that. They tired to keep it secret for many years.

Actually one of the Vulcans landed at Plattsburgh AFB after "nuking" NYC. I'll bet they did not get a warm reception.     

[med6753]

The Type 422 is done. Just minor calibration/compensation adjustments required. It's now on the torture rack for burn-in.

Scope B/W is 15MHz. 1MHz square with sweep set to X10 MAG. Not bad. And trace is much sharper than shown. Damn camera.

[bd139]

Looking good 

[mnementh]

Nice job, med. Keep saving those hollow-state beasties!

mnem
 

[mnementh]

Mildenhall Osprey on a training exercise practised landing yesterday at Cambridge Addenbrookes Helipad and on take off the wash from its twin rotors destroyed the helipad  , something that our Heli-Med copters don't do 

https://www.cambridge-news.co.uk/news/cambridge-news/addenbrookes-hospital-helipad-damage-helicopter-20444102

Huh?!? Carnage...? It's a temp helipad that doesn't appear was ever properly anchored. Am I missing something here?

Isn't that something USAF flight engineers should know better than to try and take off with that from a temp heli landing site? Or is this hospital actually using that as a permanent helipad?

No matter who's at fault... clearly a failure in the command structure and communications channels.

mnem
"Hold into your butts..."

It is (was) a permanent helicopter landing site. It was not designed for a V22. Note the matting that was lifted is NOT what the V22  landed on or that the normal helicopters land on. They land on the grass. The matting is (was) for the transfer land ambulances to stop them getting bogged down.

Yes, it's pretty obvious that multiple people who cleared them to land at this site (and yes, I understand that the operator is one of those people) had no idea what they were authorizing.

But it also seems that the definitions of "fit for purpose" and "permanent" have pretty obviously been skirting some very close limits nonetheless...     I understand that the Osprey's propwash is going to be much higher velocity, which was the cause of the damage. I know this firsthand on a much smaller scale. But shouldn't it be expected that there should be some leeway here with respect to what wind velocity the thing can withstand? Otherwise, the thing won't be there to serve its intended purpose in cases of natural disaster, etc...

Is there something different aboot this landing pad "product" and the one I referred to earlier that it is not supposed to be anchored? That seems a very important oversight if it was supposed to be.

mnem
 

[Specmaster]

Yes there is something special about it, it is not a helipad, but a platform laid down to enable an ambulance to make its way from the road to the helicopter pad (grass) without it becoming stuck in mud. The structure is strong enough for the civilian helicopters but the v22 is a far cry from them as the down force is not only down to the wash from blades but also the turbines exhausting downwards in that configuration.   

As I mentioned earlier, the hospital is and has been for some time now undergoing major reconstruction work and I'm pretty sure that it used to have a roof mounted proper pad and believe that this was a temporary setup while the work is going on.

[Robert763]

I don't know the specification or installtion requireemnts of the matting. The "big" medevac helicopter that reguarly lands there is a H145 (Derived from BK 117 and similar to the UH72 Lakota). It weighs about 3.5 tons (max gross takeoff). The V22 weighs about 14.7 tons empty, 21.5 tons MGTO vertical. More than 6 times more. The down wash is also much higher velocity. The H145 has 95m2 total rotor area, the V22 has 211m2. this is 37kg/m2 for the H145 and  102kg/m2 for the V22.
Totally different class of aircraft. Your argument is like saying a bridge designed for an SUV should be able to take an articulated truck.

[mnementh]

No... I'm not arguing... I'm asking, because I don't know. The only time I've ever seen anything like this put down, it was in a training video and the thing was anchored to the ground as part of deployment.

Looking at this video, and knowing that, it seems that whether temporary helipad, temporary road for an ambulance, or whatever... anchoring it is a no-brainer if it has to stand up to propwash from a rotary-wing aircraft.

After that is when we devolved into what is the thrust specification for one type of aircraft or another... I already knew there is a huge and material difference between the two types of aircraft and how they develop lift, and said so more than once.

mnem
 

[mindcrime]

This board has done it to me AGAIN.  Talked me into this, you lot did. I am holding all of you personally accountable here.










Yes, I finally broke down and bought a (cheap) GPSDO. What are you people trying to do, turn me into a time-nut?!?? 

[mnementh]

It's in the water coffee... Here, take a cookie; I promise by the time you're done eating it, you'll feel right as rain... 

mnem
...and I may or may not personally lace the tacos with spec-an fever virus.

[vk6zgo]

And because I'm completely  sick, I'm now starting with R2R

Ever since I was a wee lad I always wanted a reel to reel deck - solenoid action for the dream fulfilled.  Some years ago I came upon an AKAI GX620 for a sum I was happy to spend which seemed operational except for once channel dead on playback.  I suspected the fix would be electronic and later I discovered there were "overhaul kits" containing semis and caps as items of the era were prone to needing such action.

So ... one day ... I will get around to giving it the attention it deserves and I will have it proudly displayed with a couple of 10" reels - and then show it can play music (to the probable disbelief of the younger generation).


It is, however, missing one of the thumbscrews that retains the head cover panel.  Other than that, it is rather good cosmetically.

I gave up on Reel to Reel for home projects many years ago, when, in a weak moment, I bought a Uher which had been through a Cyclone.
Apart from a generous layer of red dirt, the thing was missing a front panel & various other useful bits.
I managed to get some audio out of it, once, then it went into the shed!

The only R2R stuff I did after that was with the Beyer(later Rola) things they had for emergency programme
sources at various AM Broadcast Tx sites.

[vk6zgo]

Note 2: Told some of my ham friends I got this power meter (they know what I do over here, some have visited). I said it isn't a "Ham" thing like MFJ stuff it's legit lab equipment and wasn't made for "casual" ham radio use. But it certainly can be used for that hobby if I wanted to. One of them asked me how much power it could measure. I said, well the sensor can measure from -30 dBm to +20 dBm without attenuation. He said that +20 dBm sounded like a lot of power.

I said - don't get one. That's me - saving power sensors for posterity - one day at a time. 

You actually let some of those Hobos in your house? Did you have to fumigate afterwards? 

I'm one of those hobos!

More on topic, & onto non ham matters, back in the day, for the lower powered analog TV sites (around 2kW), we used a HP410c & a special pickup "tee" (can't remember the hp part number of that), read the RMS value of the RF, then calculated the Power with a calculator (a hp one, of course!).

This translated OK as "sync tip power", as the 410c probe is a "sample & hold" type of detector.
As there are no amplitude variations on the Sound carrier, for that, it gave average power.

I have a 410c, & have been looking for the "tee", but I think, even if I get one, the setup might be too insensitive for ham power levels.

For higher power sites, the default was a water cooled load------knowing the flow rate & temperature rise, we could calculate the average power, then knowing the amplitude of the syncs, we could further calculate "sync tip power".

We did have one of the HP RF level meters which was good for lower level stuff, but it got little use, as a spec an could get us to around 1dB accuracy.

The tee is either hp 455A or later part no. 11042A, here are a pair I bought to go with my 410B/C voltmeters and a 458A (aka 11043A), BTW all these parts are listed in the 410C manual.


David

Thanks, David.
Yes, I knew they were listed, but was too lazy to either search for one on this "iCrud" device, or turn on the "real computer" & look at the downloaded file!

I still have to mess with the 410C a bit to refurb the DC probe, but apart from that, it has been a good buy at $A40 from the local Hamfest.
The tees are "rare as hen's teeth" in Oz, though!

I really have to dig around in the junk & find all the various other RF gadgets which I have picked up over the years, which include a very nice Siemens directional coupler, & a couple of similar units of unknown provenance.
I would dearly love to pick up a 7L12 or similar Spectrum Analyser plugin for my Tek 7613, but such are usually overpriced.

My ham radio based measuring does not require any great degree of accuracy-------"in the paddock" is usually close enough.
Cheers, Bryan.

[vk6zgo]

And nicked all our actors to make it. 

Still, back in the day, you Poms used to steal all the Oz actors, & send us stupefyingly bad TV shows in exchange:

"Some Mothers Do 'Ave 'Em", anyone?
or
"Love Thy Neighbour"
or
" Are You Being Served?", etc.
(& they were amongst the better ones----- there was one with some weird kaftan wearing secret agent/detective the name of which I forget, which really plumbed the depths)

We, in turn, filched actors from NZ.