Puma pit stop, airborne wheel changes.

[NutLoose]

I remember similar in the RAF in the seventies with a leg.

LiveLeak.com - Helicopter Puma SA330 with landing gear problem gets repaired in the air

[Fareastdriver]

Ii looks like a nice publicity thing. It was obviously laid on for the bloke in the big Mercedes in the backgound. After over thirty years experience on various marks of Puma, including burst tyres, I cannot think of any requirement for wheels be changed in the hover.

Obviously a goody goody exercise. The incident in the seventies was a Wessex undercarriage re-installation because the previous incumbant had departed company with the aircraft.

[dragartist]

Was there one put down on a stack of pallets or was that the Chinook following the carrier incident where they took the back legs off.

[D120A]

We replaced the main starboard undercarriage leg on a Wessex at Odiham in 1967, after the aircraft arrived in the circuit with it very broken after some extremely effective terrain-following flying on Salisbury Plain.

We had no spare, so the replacement item had to be robbed from an aircraft in the hangar. The Wessex was refuelled in the hover (Wessex in-flight refuelling!) and the pilot changed several times. I recall the whole exercise took over an hour. Afterwards, the paperwork took considerably longer...:}

It was a cold day, and working in the rotor downwash for a length of time in such conditions is a numbing experience. First (and last) time I have sought out the exhaust plume of a Gnome at full chat and ignored the smell, just to warm up...:bored:

[Cows getting bigger]

dragartist - SW managed to 'trap' the back edge of Ocean some years back whilst steaming around the Med. It was about that time that we stopped doing running landings on grey things that moved. :eek:

I've also a vague recollection of Chips Carpenter having a Puma undercarriage faff on 230 Sqn in the late 80s which involved engineers, crow bars etc.

[ShyTorque]

I watched at Forus heliport as as one of Helikopter Service AS's Chinook's rear u/c legs fell to the ground as it lifted to the hover, full of pax. Took them a long time to sort it out. It was eventually put down safely in the maintenance area, on sandbags.

The Puma HC1 was designed with the ability to land wheels fully retracted. Then the RAF put various aerials on the underside, which complicated things. We used to fly round with a "sandbag plan" in the bits box in the event of the gear not coming down but I don't recall one ever being used in anger. However, one Puma (33 Sqn's rather than Chips' one) was set down wheels up but undamaged on the grass at Odiham, rather than on sandbags, after holes were dug in the ground to accommodate the aerials. It was later lifted by crane. I remember peering round the side of the Met office building to watch the fun, thinking that would prevent me having to attend any subsequent Board of Inquiry, other than as a witness, if it rolled over. All very eventful though.

[charliegolf]

John Gill and I once turned a 5 min air test into a 1:30 'Is it down and locked or not' flight when we only got 2 greens. We had to refuel in the hover, as I recall. I also recall a trailer with Shy's sand bag layout on it being wheeled out, but we didn't use it. The engineers decided it was indeed locked and we landed on the grass- we didn't taxi in.

CG

[NutLoose]

I was at Aldergrove when I think it was AT had a leg failure, that was put down on sandbags which came in handy as the nose door was then swopped for a erm damaged one off another cab.. I remember we set them up then ATC asked us to move them as it would block the runway when it fell over... It must have really been a moral boost for the unfortunate pilot.
Ohh and D McD never picked up that nights film from the Pongoes even though he was there when it failed :( :E

[Fareastdriver]

All the Pumas I have seen worldwide have a VHF ariel mounted on the bottom starboard nose which would suffer in a wheels up.

An interesting one I had in the mid 70s was a nose oleo overrunning. Previous to that the nosewheel would come down at the same rate as the mainwheels. Sometimes, as in this case, the inertia of the nosewheel would cause the jack to fracture and the piston would overrun causing the gear to jam in the over centre position against the side of the nosewheel bay. Then all the hydraulic oil on the No 1 system would follow it.

It had happened before and I had thought about it so when the bang came and the light turned red I pulled the Emerg Hyd handle that isolated the No 1 Hyds. I then landed it because the undercarriage was safe against the bay wall.

This happened at Thetford so I got onto the blower and told the squadron at Odiham all about it. They then asked me to fly it back!!!!!

You can cocoa.

The modification was to put a restrictor in the nosewheel jack so that is why it travels more slowly than the mainwheels. Strangely, it wasn't done to the civvy ones, probably because they don't cycle the undercarriage so much.

I still cannot understand why RAF pilots have to climb over the jump seat to get in the cockpit whereares the rest of the world get in through the cockpit doors that the manufacurer provided.

[antisthenes]

Because idiot Pongo LOs and little boys at airshows had a habit of using the black and yellow handle and the engineers got very tired of having to re-do the wirelocking once they'd fallen off!

Also, if you had a nav bag with complete 250 thou coverage, the Helilanes et al, it was easier to lug it in through the cabin than over the seat. This obviously didn't apply to the wasters in RAFG who only had a map to get them to the next Tiger meet or once Navs arrived.

[Cows getting bigger]

Maps? Wasn't that the role of the Doorman?

(Doorman - term used by the Stn Cdr during one Monday Morning mass brief) :}

[lsh]

Whilst "Fareastdriver" has much, much more Puma experience than me;
I was always taught not to put "Puma" & "Door" in the same sentence, they caused so many problems.
The more you move them, the higher the risk that they fall off; in my view.

If I got to do nothing else before we got airborne, I always checked all 4 doors and the main cowling carefully.
(And NEVER hang the ladder on the side "overnight".....!!)

That said, a very experienced operator indeed told me just a couple of months back that they "could not use the main doors, because of the kit in the back" and therefore used the front doors, "needs-must" I guess.

lsh
:E

[charliegolf]

wasters in RAFG who only had a map to get them to the next Tiger meet or once Navs arrived.

Ah, helicopter navs- handy for compass swings and ... No, just compass swings.:ok:

CG

[jayteeto]

Bob Gibbs mangled an undercarriage at Caye Chapel in Belize. That required a hover wheel change as we didn't have facilities to jack the aircraft up. That certainly was not a 'goody goody' exercise. I'll have a dig around for the photos.

Sporty landing to do it..................:ok:

[TBM-Legend]

Watched a Malaysian Air Force S-61 Nuri hover for nearly two hours [including a refuel in the hover] while the ginger beers extracted an oleo and changed wheels and effected a hydraulic repair after it was shot-up in the non-war of 1975 at Butterworth...

[ShyTorque]

Quite a number of years ago, on leaving the HUET (then in the submarine escape tower) at HMS Vernon, a group of us watched a newly introduced-to-service (this ages me) Sea King being marshalled down from the hover to a landing on a concrete helipad. We immediately noticed that the u/c wasn't down. We yelled and waved to no avail, the marshaller had his back to us. A loud clattering noise obviously woke up the crew and the marshaller (who must have thought that Sea Kings didn't have wheels). Having briefly made metal to concrete contact, it shot up to a hover again, the wheels came down and it landed. Oops.

[Fareastdriver]

We yelled and waved to no avail

Not half as much as the Station Commander, Squadron Commander and assorted VIPs were waving and shouting at me at Odiham.

I had gone to Pershore to fly Mike Butts aircraft that was fitted with a forward looking TV. The boffins had fitted it in the hanger through the load pole hatch when it was on jacks in the hanger. Fantastic, they thought, with this perfect picture in the cockpit looking straight ahead.

Then they lowered the undercarriage; and there was a perfect picture of the back of the nosewheel.

This required a slightly different operating technique inasmuch as soon as you lifted into the hover you retracted the gear to see where you were going. We then proceeded to try to navigate to Odiham.

Having got lost soon after passing over Pershore's boundary fence we were fortunate to have the M4 show us the right direction. We then stumbled south, found Basingstoke and then North Gate. I then set up a left hand approach to the southern perimeter track to 33 Sqn dispersal on the south side of the airfield. I then reversed the undercarriage technique by leaving the gear up until the hover so we could see where we were going.

The grass on the western side of the hanger was the site of a tactical camp we had erected for demonstration purposes. Unbeknown to me there was a VIP visit and they were looking over the site as I approached them with the undercarriage up. Apparantly they were trying to indicate this to me with some desperation and when I did finally lower the undercarriage in the hover a fair number of cardiac arrests were prevented.

The TV was a waste of time. You had to fishtail the aircraft to get any sort of track verification and on the demo trip that afternoon half of Ops Wing were airsick.

[Fareastdriver]

Shy Torque mention Pumas with the gear retracted.

The 332 Super Puma and later had the 'kneeling' undercarriage. The mainwheel oleo was in two stages initially to allow it to accept an 8 m/s (900 ft/min) landing velocity for carrier operations. Should the undercarrige be pumped down using the manual emergency system only one stage would be pumped down leaving the wheels locked halfway down.

This system gave a bonus inasmuch as the the aircraft would sit with its backside down making it easy to load load freight through the back and lowering the pylon so it was easier to load into transport aircraft. This avoided the Puma trolley allowing to aircraft to be towed in and out on its wheels, as has been done in the civil world dozens of times.

I landed on a platform in the South China Sea and my co-pilot, on his look around, discovered an hydraulic leak from the starboard undercarriage. I shut down and as it was a British registered aircraft I got on to the chief engineer. He asked me where the leak was from and I couldn't answer that because it was everywhere. He requested I have another look so back I went to the aircraft.

I wiped everthing it sight but there was still no trace of the leak so I thought of a way of pressurising it to get some oil to come out. On the 332 the emergency undercarriage pump lever is in the middle of the floor and you pump laterally. I switched the battery on, checked that the three greens were on, pulled the emergency lowering handle and started pumping.

(all 332 qualified A&E engineers are now holding their heads in their hands)

There was a loud berdoomfda and both undercarriage legs collapsed to the kneeling position.

I was frantic about my co-pilot in case he was under the leg when it happened but there were no casualties. I thought, and everbody other pilot I knew thought, that the undercarriage was inviolate when down with three greens as selected. I got back on the blower and told the engineer what had happened. He knew all about it; it was a dodge to get the aircraft to kneel before loading it in a 747.

I then indicated that I was fed up of doing his job so I sat there until they winched down some engineers.

If it had been a Chinese registered machine there would have not have been a problem. Pilots are not allowed to get their hands dirty looking for leaks, that's an engineer's job.

[ShyTorque]

I thought, and everbody other pilot I knew thought, that the undercarriage was inviolate when down with three greens as selected. There was a loud berdoomfda and both undercarriage legs collapsed to the kneeling position.I recall a similar incident when the G/Cs at Gutersloh were pumping up the brakes accumulator of one Puma HC1 in the hanger, before towing it out onto the line.

Something in the system hadn't cycled properly and as the line mechanic pumped the handle on the left of the copilot's seat, there was a thud and the aircraft began to retract its undercarriage and began sinking to the hangar floor! None of us knew that was possible (and it shouldn't have been but that's hydraulics for you).

Especially embarrassing for the engineers as many of the aircrew were walking across the hangar to met. brief.

[Tiger Tales]

Skip to the action at 4:00

PJgGQ0ttke8

[stumblefingers]

I think that was me, and yes one bit of kit we operated totally blocked passage from the cabin to the cockpit, so we had to use the starboard front door (the left one was just a jettisonable panel). However, there was a good reason why this was not SOP, as at least 3 times I had to take control of the ac and land it in a field whilst my pilot hung onto his door for grim death after it had come open in flight!

This will not be a problem with Puma 2, as there are no front doors at all.

[BEagle]

I recall a tale from the early days of these Anglo-French clattering things....

It would appear that some part of one of these device's gubbins wasn't working as advertised. So a decision was made to change it. The part in question was prominently labelled 'Gonflée a l'azote', which meant nothing to the oily baldrick who was attempting to remove it....

Finding it difficult, he decided to find a bigger spanner and to disassemble the errant item in situ. This proved more difficult than he'd expected - that is, right up until the last couple of turns. Whereupon there was a load bang, or rather 'boum' and the thing flew apart, releasing all the 'azote' with which it had previously been 'gonflée'.....and nearly taking his head off.

It was then decided that 'Charged with nitrogen' rather than 'Gonflée a l'azote' would perhaps be a more useful label on RAF aircraft.....

[ericferret]

There is a tale that a collapse similar to the one described by SHYTORQUE happened to a Schreiner SA330 in Nigeria. After the collapse an engineer stated that this was impossible to induce. He climbed into a second aircraft and repeated the operation, sadly with the same results.

Would be nice to know if this story is true or not as it's been doing the rounds for years.

[Tankertrashnav]

I remember getting a huge belt of static electricity as I touched the airframe of a Whirlwind when helping to load some kit into it while it was in the hover.

Is that a normal hazard in these kind of occasions, or is it normal to earth the static first before setting to with your wheel change, or whatever?

[charliegolf]

TTN, it's normal. Underslung load operators usually earth the aircraft with a wand and spike affair before attaching the load. Puma not so bad, I hear the Sea King was/is a bugger.

CG

[Jumping_Jack]

Wasn't there a Chinook incident involving a broken droop stop on the MRB? Hot refuelling whilst a ramp was built up the side of the fuselage to prevent the blade doing a 'Moulinex Multichef' as it eventually slowed down? :eek:

[lsh]

Pulling the Emergency Undercarriage handle on the Puma HC1 also did some electrical gubbins (by-pass weight on microswitches?) and certainly needed pulling fully up to get it all working properly.

We did a demo to each OCU student crewman, who pumped the u/c down manually. (Leg 1 easy; Leg 2 harder; Leg 3 sweating!)

It was part of the full airtest schedule too.
I think we just reversed all the selections, post-test.

System was also used to retract the gear for the Herc loading for Belize etc.

lsh
:E

[sandiego89]

Wasn't there a Chinook incident involving a broken droop stop on the MRB? Hot refuelling whilst a ramp was built up the side of the fuselage to prevent the blade doing a 'Moulinex Multichef' as it eventually slowed down? :eek:

Yes there was, discussed here: CH47D Droop Stops Failure Procedures [Archive] - PPRuNe Forums (http://www.pprune.org/archive/index.php/t-469396.html)

Not sure if the current proceedure is to do something similar, or run and let the beast beat itself to death....

[Fareastdriver]

On the Bristol Sycamore the control runs for the squash plate went though and out of the top of the rotor shaft. The droop stops and indicators were on the top of the head so could not be reached whilst the rotor was turning.

During shutdown the pilot would use a mounted mirror to ascertain that all the droop stops were in (Red soldiers standing upright) before shutting down the engine. Should they not then he would exercise the controls and this nearly always caused them to engage.

However. Should they not engage there was a problem because the blades would fly into the boom. The mass balances on the end of the blades also ressembled 20 mm cannon shells so they would cause more even damage. There was a thick piece of leather stuck on the critical point of the boom but its protection could not be guaranteed.

So you called out the Fire Department. One stalwart would crouch down by the starboard side of the boom and aim a powerful jet of water just over the top of the boom where the leather decoration was. Once this jet was establish the engine would be cut and as the blades slowed down they would ride the water jet over the boom.

The blades were made of wood and they were not designed to have water pumped up their backside so they were invariably scrapped.

[oldgrubber]

We had a Seaking that a pilot had managed to bounce hard on the Lusty (I think), as he was doing DLPs. as he took off again the tail wheel and oleo swung out gracefully by the tail yoke, disconnected at the top end. As we rushed around sourcing a new oleo from the ships store two of our strongest maintainers, a PO grubber called Frank and a Chief Tiff called Dave went out to assess the damage whilst one of the guys earthed the aircraft with an earthing pole to the sponson lashing point.
It quickly became apparent that the casting inside the housing was broken so Frank and Dave informed Flyco that the plan was to hold the broken oleo and associated gubbins up inside the tail oleo housing as the aircraft landed. This plan worked beautifully apart from Frank getting a great belt of static when the lad let the pole disconnect at the precise moment he touched the yoke, but he claimed afterwards that it cured his muscle pain in his shoulder!

[Mickj3]

I heard a tale back in the 60s of a wheel change carried out at Odiham on either a single or twin pioneer doing a low slow pass and the change being carried out from the back of a landrover driving along beside it. Any further info?

[ShyTorque]

I heard a tale back in the 60s of a wheel change carried out at Odiham on either a single or twin pioneer doing a low slow pass and the change being carried out from the back of a landrover driving along beside it. Any further info?

Which hole in the far hedge was that one from?

[NutLoose]

We did a demo to each OCU student crewman, who pumped the u/c down manually. (Leg 1 easy; Leg 2 harder; Leg 3 sweating!)

It could have been worse, I did an airtest on a Beech Baron many moons ago and the requirement was to hand wind the gear down, the crank being awkward to get to and located behind the seats.
The pilot started to crank it as I held the aircraft steady, looking at his face getting redder I suggested I should take over.
Swinging round and reaching behind the seats I continued to crank the gear down as both of us cursed Beechcraft and their stupid design, the language was quite fruity and involved a lot of swearing between us, unfortunately during the said exercise and unknown by either of us, my knee was pressing on the hand mic between the seats and we were transmitting :O
There must have been some laughing going on at Waddington, because after telling us we had a hot mic post gear drop, we never heard another thing about it. :O

[lsh]

Well "JD" was making very heavy wx of pumping the u/c down, and I must admit it was well beyond the "70 pumps" needed; at around 100 I leaned over and had a go - SOLID!
We reversed all the selections and snagged it.

Laugh.....I nearly passed him!! (He was our new Boss :O)

lsh
:E

[charliegolf]

I heard a tale back in the 60s of a wheel change carried out at Odiham on either a single or twin pioneer doing a low slow pass and the change being carried out from the back of a landrover driving along beside it. Any further info?

Bull****! A Twin Pin could never keep up with a Land Rover! Tut Tut!

CG