Brilliant commentary! One little "rain on your parade" might be the condition of diaphragms in the carbs. I am not familiar with the Hercules carb, but if it is anything like a Pratt & Whitney, if they are dry for too long, they do what rubber does. Perish. It only occurred to me when you mentioned the refuel. Hopefully the Brits designed a different carb, or it has been wet since being parked at Omaka? I hope it all works for you. Tony
Post by Radialicious on Jun 4, 2008 21:21:51 GMT 12
Thanks Tony, Yep the carbs could be the fly in the ointment. Those that were responsible for her back in the day insist that all steps were taken to preserve everything. The STBD carb had quite an oily jippers inside it where the port one was clearly old AVGAS. I guess that if it isnt dry inside, the diaphragms might stand a chance. I don't really know what their purpose are but am hopeful that the idle circuit doesn't need anything too tricky to make the engines run. Oil pressure is used as a servo for automatic boost and mixture control circuits. I visited the old 4TTS last week to study their cutaway Hercules carb. It is a work of (Pommy) art. Most things on this machine are known quantities. The carbs aren't but there is a good way to find out.....
Post by Radialicious on Jun 4, 2008 22:04:36 GMT 12
Funny you should say that. Fire is my biggest fear and I've managed to establish quite a reasonable response to it if it should occur. Big Bird is a lot of fun but doesn't belong to me so I gotta be careful! I'm gonna invite the local fire brigade to B-day - hopefully they will bring at least one suitable appliance...
Post by Dave Homewood on Jun 5, 2008 20:21:55 GMT 12
Brilliant photos there Craig, well done.
When you look at the aircraft in detail like that you realise that there is a fair bit of surface corrosion and deterioration from its years out in the elements, especially in that cockpit area. I hope that perhaps the engine runs generate enough interest for a project to get together to refurbish the whole airframe. I realise it would be costly and beyond one man's efforts such as with the current project. But it is certainly an excellent piece of history and it would be a shame to allow it to contine rusting outdoors. Perhaps a building could eventually be fundraised for too. Just some thoughts, not meant as undermining the current wonderful efforts of either Al to re-ignite the beast, nor MAC in saving the aircraft from the scrap heap.
Post by Radialicious on Jun 6, 2008 22:18:01 GMT 12
Craig, there isn't much that can't be done on our airfield! I asked Tony if he could put my Super-Pommy-Plug on his website in the hope that I could market it to other Bristol B-170 owners both locally and abroad. He declined in the fear that a flood of orders could clog up his workshop. ;D
You are right Dave, she has suffered a bit over the years as a static guardian of our airfield. In many ways she has been neglected and hopefully this project will make her a bit more deserving of a bit of love and attention. Who knows what may yet happen to her. I take my hat off to her for lasting so well. Built in 1953, she has probably only ever spent a total of a few weeks under cover in her life. There are many photos of her in her hey-day (before her hay-days) and I'd love to see her dressed up as bright and shiny as she once was. The Argosy at Woodbourne is inspiring because she still looks glossy and fresh in whatever paint she is wearing.
I didn't achieve a hell of a lot (perhaps) today. The Omaka AHC was a port of call today to study up on some routine inspection schedules in their library.
Marlborough Helicopters offered me the use of their battery cart(s) next week. That will be a great help. John Sinclair (their former Managing Director) was directly responsible for securing her from the scrapheap. He still remembers (most bits of) the drunken night with the then GM of SAFE Air after CPT was safely flown across to Omaka. He and that GM intends to be front row smoke-sniffers on the day.
My good mate Marty Nicholl has offered to jump on his Bernina and sew up some canvas covers for the cowls and spinners.
I have the weekend off and hope to square away a few more of the last little technical jobs so that I can concentrate on the more logistical tasks next week. I think I'll look at the pneurotic system in an effort to have at least some means of braking. Our chocks are more than reasonable but again, it's not my machine. The tail is chained to the ground but there was once a crew who forgot the tail pickets at Woodbourne. They assumed soft ground was the reason they initially had difficulty taxiing. A passenger complained to the steward that he could see through a hole in the toilet floor. The steward explained all about the myriad of drainage holes toward the tail end. The passenger knew what he was talking about and asked that it get looked at. Sure enough, a LARGE hole was in the place of the structure that held the tail tie down rings which were still chained to the ground in Blenheim.....
Owen Hughes told me of the day when the voice of a new female air traffic controller came across the radio in Blenheim. Owen and his F/O spent their shift pestering her as to what she looked like. Being new to the job she kept that kind of info to herself. By the end of the shift, curiosity had got to them and on the last sector they taxiied as close to the control tower as they could get. With the wing-tip hard up against the tower, they shut down, popped the escape hatch and climbed out on top of their Freighter. It was a short walk out to the wingtip where they were able to press their faces against the glass of the tower and perv all they wanted at the object of their curiosity! I am fairly sure that the F/O that day was the now senior Captain that I flew across the ditch today. Kevin Hodson is a well known old school larrikan in the regional airline circles. There are many many stories about this man. My favourite is his address to the cabin of a Beech 1900 when he was training a new Captain. Acting as the First Officer, he asked the passengers to ensure their cell phones were off. As he walked down the aisle checking seat belts and cabin bag stowage he paused halfway. He told his audience that there was a good reason why cell phones needed to be turned off. "Folks, we have gear in the cockpit that can recieve cell phone calls. We are sometimes pretty busy up front and if we take a message for you, we might get it wrong. Your missus might call and ask you to get milk and eggs on your way home. We could jot it down wrong and you'll go home with milk and bread instead and get in trouble. For that reason, please ensure all cell phones are turned off".
I have a vhs on the Bristols of Safe Air. although I would guess that you all would have seen it,however it shows one of the Freighters on a run to the Chathams and tells the story of the then new installation of the crew toilets. It appears that the Captain or the F/O(one or the other) went down to use the newly installed implement and the Captain called the Steward up to the cockpit, The plane was fitted with one of those passenger capsules? and when the steward opened the door the passengers were presented with the sight of the pilot going potties.
Al, I was wondering if you have thought about what happens in the aircraft electrical system when you run the engines/generators with no Internal battery connected?? The generators might need an internal battery connected just to act as a load for the generators to prevent them running away/going into an overvoltage situation. On the other hand they may need an internal battery connected to "flash the field" to get them on line, so if you have no battery then they may not come on line at all? I have no idea how the Bristol electrical system works but you might want to do some homework on it before you fire her up so you don't do any damage to the electrical system. If you don't need an internal battery connected to run the engines then make sure the battery leads are secure and not going to touch anything!
2TTS at Wigram had a full working mock up of a Bristol Freighter electrical system when I did my Techs Course. If it is still at GTW you might be able to find out how it all works there.
When you get to the point of taxiing the aircraft you will definately need an internal battery
Post by Radialicious on Jun 9, 2008 20:55:48 GMT 12
Thanks Don, you are dead right about the electrical system. I am slowly learning the very basics about what goes on and how. You are dead right about the generators. I have considered not even using them. Each has a field current circuit breaker that I assume when tripped will disable them. There is a hell of a lot of real heavy (and old) wiring/cabling running in out and around the cockpit, inner wing and the nacelles. I'd prefer to have the gennies as ornaments only just to keep the high amperage thingamy's to a minimum. The battery currently lent by SoundsAir is ample to run the low draw components and systems after the engines have been started using external power. The port engine genny isn't even wired into the electrical system. I'll e-mail Malky Hamilton and see if the Freighter training aid still exists. BTW speaking of GTW, they are currently looking at replacements for the Devons and maybe the Strikemasters as training airframes. It will be interesting to see what comes of that. Having trained on the Devon at 4TTS, I'll be tempted to look whether or not it would be sensible or practical to consider tendering for one
b10m, I too have that VHS doco on the end of the Bristol in NZ. It is a good record and the engine starting sequences are very inspiring.
Today, was an interesting day. Over the weekend, I got a few more jobs squared away. One was the oiling up of the STBD system. Like the port engine, I wanted to drain the old oil from the sump. After learning a lesson the first time, I was a bit more careful this time around. The spring loaded sump drain valve was so completely scunged up with scungey old scunge that very little of anything actually drained out. That wot did looked alot like either water or the Jet A-1 that I used to proof the fuel system. In typical blokey workshop fashion I 'tasted' a drop on the end of my finger. It was foul and gross etc etc but was certainly more watery than oily. There was very little to speak so that was OK. I may have written in the past about the STBD engine driven fuel pump that had an internal leak from the drive cavity drain. As a short term measure, I had blanked the outlet to stop the leak. This had made me suspect now that the fuel leak mightn't be contained and could end up leaking into the accessory section. There was no easy way to de-scunge the drain so I chose to remove the sump filter. I'm very pleased that I did because after a few pints of oil, a flood of Jet A-1 gushed out of the filter cavity. Sure enough, my suspicion was correct. There was no way I could ignore a fuel leak into the sump like that. The pump came off with littte drama and was quickly on the bench in the workshop. I didn't have a manual for this one but it was clear there was evidence of a leak. My research on this pump hinted at a 'Morganite' drive seal. The -ite part of Morganite made me wonder if there was a carbon seal in there. The translation of 'English Carbon Seal' is 'Can Of Worms'. The drive end of the pump came undone reasonably easy and sure enough there was a carbon seal that mated with a ground steel face. The steel face had a reasonable of concentric wear pattern that I thought was the obvious source of the leak. However, futher disassembly found two very hard, very old rubber O-rings. These were inside a four piece floating drive adapter between the quill shaft in the accessory case and the rotating element of the pump itself. The O-rings appeared to seal either end of this adapter. I discussed with Tony W whether or not to lap the wear out of the steel face. We soon came to the conclusion that matching wear was on the carbon face also. It was clear that any leak past the delicate carbon seal would be minimal compared to what could get past the O-rings. We found some new O-rings and I reassembled the pump. It is now back on the engine and after Big Bird is refuelled tomorrow, I'll look forward to hopefully finding no leaks. That will be the beginning of the fuel system flush and bleed that is required before B-day. Hopefully Friday is B-day. We'll see........ Fingers crossed.......
Post by Dave Homewood on Jun 10, 2008 18:30:38 GMT 12
I have just been having a think, and I recall that during one of the Wings and Wheels airshows when i was living at RNZAF Wigram, and I think it would probbaly have been the 1992 one, the RNZAF Musuem got all its aircraft out of No. 6 (Storage) Hangar and had them lined up near their No. 7 Hangar restoration workshops. I have the wierd vague feeling that they ran the engines on the Bristol Freighter. I am not certain, and it might have been one of the 2TTS Devons being run for the crowd, but I recall walking past where the historic aircraft were lined up and something was running. At the time it meant nothing to me really, so passed by as I was 'on a mission' (lunch I think).
Does anyone else recall this? Some of you were probably at that airshow, do you remember?
I know I have a photo of the Bristol and the Corsair etc outdoors I took that morning. But not of it running.
At any rate, i know the Museum used to run the engines on the other Bristol they had, and maybe '03 back in the olden days. I wonder if there's anyone who worked at the museum then that might take an interest in (hopefully) Friday's run?
Al, did your father ever run the Bristols at Wigram when he worked there?
Post by Radialicious on Jun 10, 2008 22:31:10 GMT 12
Today was an interesting day to say the least. It has been many many years since Air BP filled out a fuel delivery docket against the registration ZK-CPT! The refuel went without a hitch as Rob from Blenheim airport brought his tanker to us early this afternoon. It was way easier to do that than take Big Bird to the pumps......... 201 litres later, CPT had fuel in her wings for the first time in a long time. Allan Udy arrived in time to record the process on video. It was interesting to note that the fuel gauge on that tank registered 44 gallons the next time I turned the power on. Yet another system that has woken up from an 18 year snooze and is ready to party. I was dead keen to test the engine driven pump that I had repaired yesterday. Thankfully she was leakfree and is now keen to join the party also. Allan was there to capture me trying to de-scunge the engine sump filter cavity. There was an awful lot of the most foul rubbish that I scooped out with both my fingers and the blade of a screwdriver. If I was able to, I'd really like to remove the whole sump and huck it out good and proper. It does appear however that there is a serious lack of access inside the cave in this area. The scavenge pump however takes oil from a level quite a lot higher than the scunge so I am confident that is where it will stay. The toilet ballcock in the sump will only open the scavenge system when the oil reaches a certain level. Gavin Conroy also showed up today and was a huge help when it came to flushing clean fuel through the fuel system. It is impossible to be in two places at once on a Bristol and another pair of eyes and hands was a great help. I've got a few pairs of hands coming from tomorrow onwards as the big day looms. Gavins camera was able to capture some rather spectacular shots of the STBD engine being cranked over while its engine driven pump was being leak checked. I'll post them when I get near a broadband PC. It appears that I used 2 or 3 gallons to flush and prime the fuel system and both engines. Gav and I laughed as we poured about 500ml of fuel back into the tank after flushing one of the fuel pressure transmitters. There won't have been to many times in the history of the B-170 that such a small amount of gas was recycled in this manner. Mind you, AVGAS was probably not the pricy commodity back then as it is now! As Gav said often today, "she is now alive". "Also suddenly very flammable!", I thought. I guess back in the day, the amount of fuel on board wasn't really a big concern to those who operated and maintained her. Right now I am very aware of what a spark or cigarette could do to her. Now that the fuel system is squared away and there shouldn't be any significant spillage from now on, what fuel is lying around should be gone in the next day or so. By the end of play today, fresh clean fuel had found its way throughout the whole system and everything we needed to test had been tested. Even the priming system was able to be checked on both engines.
Tomorrows tasks will be a repair to an HT lead and prove the external power supply. Flying will get slightly in the way on Thursday but I finish at 12.30 on Friday. Kinda looking forward to having all the hard stuff done by then so that the fun can begin!!
Post by Radialicious on Jun 10, 2008 22:39:40 GMT 12
PS Dave, I don't think the engines on NZ 5903 have been run since they were fitted in 1988. They came from ZK-CLT which was gifted to the RNZAF Museum and eventually ended up in Canada. Dad never did the ground runs on CLT as he was a machinist and not an engine fitter. I shared the cockpit with SGT Lyn Buttle when she was being ground run and prepped for the big trip to Canada. It was a big deal for a 16 year old plane nutter. It's funny to see it go full circle 20 years later!
Post by Dave Homewood on Jun 11, 2008 0:42:37 GMT 12
Great step that, getting the fuel in. I'll bet that wasn't cheap. Congrats on another milestone.
Your talk of the flammability of her keeps bringing B-29 Kee Bird to mind. Oh dear.
I don't know what it was that was run at Wigram that day but no dount it was a Devon. They were run often, and as I said I was merely walking past on my way somewhere and took a casual interest. I know it wasn't the Corsair or spare Avenger, I doubt they'd have been capable of turning the props back then.
That must have been a real buzz sitting in the seat while they ran ZK-CLT though.