Monday, 30 July 2012

Vintage aircraft [4]

A few new clips from Youtube.
This is a Bristol Hercules engine from a Handley Page Hastings aircraft. This clip has about the best sound quality of the many clips I have seen of different aircraft engine, it is probably the most true one of the actual sound particularly in low frequency as cheap digital cameras that people often shoot with tend to have poor bass response. In case you wanted to know why it is so noisy… this engine has a cubic capacity of 2370 cubic inches and produces around 2000 horsepower at full power. By comparison a 2 litre car engine has a capacity of 125 cubic inches and produces maybe 70 horsepower. Also there are no mufflers fitted to any of the exhausts. There are 14 cylinders and because the engine is supercharged rather than turbocharged, the exhaust is straight out which means the noise level is quite high for the size of the engine, Hercules engines like Merlins were known for their high noise level and were not popular on passenger aircraft or with people who lived near airports where aircraft fitted with them flew from.
Restoring old aircraft engines and running them at public shows is a popular pastime and as we know the Bristol Freighter at Omaka has had engine restoration to allow the engines to be run and the aircraft taxied at shows within the last three years. The engineer who did the work to get it going also got hold of a spare engine which he mounted onto a trailer in a similar fashion to that shown above.
Here it is running somewhere in Christchurch City in 2011.
This clip shows the running of a Wright R-3350 engine from a B-29 bomber at night. Wright’s engines were not as good as Pratt and Whitney’s. They tended to be lower grade technology and engineering. For example when both manufacturers brought out engines around 1800 cubic inches, P&W made the jump to a two row 14 cylinder engine – Wright simply built another single row 9 cylinder engine which would have been of a larger diameter resulting in increased drag. It wasn’t until the R-2600 that Wrights built their first two row radial engine. The 2600 was the 14 cylinder version of the 3350. The latter was the biggest engine the US had when Boeing set out to put together the B-29 bomber. Wright’s decision initially to use cast fins on the cylinder head (the smaller P&W R-2800 had introduced milled fins because of the need for better cooling) was responsible for the overheating and engine fires that were such a problem when the B-29 first went into service. Although the engine design survived into the 1950s and powered the last of the great propeller airliners, they are still a less reliable engine than the R-2800 which accounts for the fact that more DC-6s are still flying today than DC-7s or Lockheed Constellations. Also Wrights went out of the engine business at the beginning of the jet age whereas Pratt & Whitney are still in business today. Technologically the largest successful radials were those with 18 cylinders. The P&W R-4360 with 28 cylinders in four rows was uneconomical for passenger aircraft operation. Wrights with the R-3350 and Bristol with the Centaurus were right to stay at 18 cylinders, although a 22 cylinder version of the R-3350 was considered. Bristol had planned several series of larger 18 cylinder engines but the Centaurus was the last model to reach production.

Sunday, 8 July 2012

Rail 150 Next Year

Next year will be the 150th anniversary of public rail networks in New Zealand. In 1988 we had the Rail 125 in which I made a bit more of a personal contribution to restoration at some of the rail heritage sites around North Canterbury. So now we will have Rail 150 and it’s interesting to note as a contrast to last time that the name “Ferrymead 150” has not been adopted.
That means we will see a great week of festivities, largely around Christchurch, which I think will include various mainline steam excursions of all kinds of characters.
Here by way of illustration is a steam excursion train heading up to Arthur’s Pass this morning, operated by Mainline Steam.
More Photos

Wednesday, 4 July 2012

Christchurch suburban bus routes to be savaged by Ecan changes

Environment Canterbury which runs the Christchurch suburban bus services, has announced significant cuts to service operations in light of the changes in usage since the Christchurch earthquake in February 2011. 

Whilst there have been some earthquake related issues this has more of a feeling of being an opportunistic change that is designed to implement overall cuts to bus services, rather than being out of necessity following the earthquakes.

The changes being currently consulted on until 3th August will basically have the following effects:
Old Route Typical Old Frequency New Route(s) New Frequencies Notes
8 Hoon Hay – Casebrook 30 min daytime 1 plus 108 30 min peak / 60 min other Route 1 higher frequency
9 Wairakei 30 min daytime 1 plus 109 30 min peak / 60 min other Route 1 higher frequency
11 Westmorland-Styx Mill 30 min daytime 111 plus 1 plus 108 30 min peak / 60 min other Route 1 higher frequency
12 Northwood-Cashmere 30 min daytime 17 30 min peak / 60 min other May not need any transfer
14 Dyers Pass-Harewood 30 min daytime ? No new service to Dyers Pass
15 Bishopdale-Murray Aynsley 30 min daytime 115 plus 1 plus 131 60 min all times Route 1 higher frequency
18 Huntsbury-St Albans 30 min daytime MF/60 min SS 17 plus 132 30 min peak / 60 min other
20 Burnside-Barrington 30 min daytime MSa/60 min Su 120 30 min peak / 60 min other May not need any transfer
22 Spreydon-Redwood 30 min MF/60 min SS 122 plus 1 plus 120 30 min peak / 60 min other
46 Marshland-City 30 min MF/60 min SS 133 plus 1 60 min Route 1 higher frequency
90 Rangiora 30 min MSa/60 min Su 1 Similar Now runs to PMH instead of city
The real reasons for the loss of patronage up to this point have been due to a combination of the following:
  • Bad roads causing slower operation, route changes and partial closures
  • Loss of the bus exchange and the resulting temporary operations out of TWO city interchanges with very poor facilities and congestion
  • Central Station is a much poorer facility more reminiscent of Cathedral Square compared to the fully undercover Bus Exchange.