Air Conditioning Washers

After solving previous air conditioning problems with a bearing and hub redesign as I outlined in this this blog post, we discovered last year that some of the new washers that were being used on the new hub assembly were failing. They would split or break and eventually fall off. Fortunately due to the new design of the 3 piece bushing/washer, this was not causing any permanent damage to the air conditioning system, but it definately is a nuisance issue.

After working with the vendor to investigate the problem, it was determined that the washer being used was not quite up to the temperatures in that area. New silicone washers (21119-112) have been designed and tested and should be available soon are available now. Until then it is recommended that you check these washers regularly and replace them as necessary.

New washers

Keep in mind that there are now 2 different hub assemblies out there and that this particular washer issue only applies to the new hub assembly. The solution I talked about back in 2010 applies to the original hubs which were replaced in late 2010 by these new hubs.

Hub Assembly with Missing Washers

Updated 4/26/12 to say that the new washers are available.
Updated 5/14/12 with the Cirrus part number and a picture of the new washers.

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60/40 Rear Seat Part 1

I have been meaning to tell the story behind the new rear seat that we have started installing at the beginning of the year. Adding a 3rd seat belt in the back has been a common request from sales for several years. We have done a couple of mock-ups over the years, but the project never advanced any further than that due to other priorities.

That changed in early 2010 when we built another mock-up and started to seriously scope out the project and define the features that it needed. We knew we could take some significant weight out of the rear seat with a redesign, and make it more comfortable at the same time. With an official go-ahead, Engineering started to design the new seat, structural changes, and interior pieces. It still took about 15 months from that point until we had new seats in production.

The initial scope included 60/40 seat back split, more comfortable seating, recline, 3 point safety belts and the associated changes to go with adding a 5th seating location like a 3rd headset jack for the back and an extra oxygen port. The scope changed some over the course of the project. We added LATCH anchor and tether locations, more recline than initially designed and a cargo net in the back.

Designing a seat for modern aircraft is not an easy task. The testing loads and occupant protection requirements are clearly spelled out in the regulations and guidance, but when trying to add fuctionality, reduce weight, keep R&D and production costs in check, all while maintaining a schedule, it becomes an incredibly challenging design problem. But as engineers, this is what we live for!

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SR22T Cabin Air Coupler Rigging

It was discovered during a production flight test that the cabin heat seemed too hot, and that even turning the heat off (vent only), there still seemed to be some heat coming through. Coincidently, that same week we had a complaint that even with an OAT of 40F, the pilot had to turn on the air conditioning to keep the cabin comfortable.

Investigation revealed the same problem in both airplanes. On the firewall is a mixing box that mixes the heated and ambient air before it enters the cabin. There are a couple of electrically actuated valves that control the flow of heat into the system. In some cases, these were improperly rigged and the valve allowing heat into the system didn't close completely which means warmer than normal air enters the cabin.

This issue is less likely to be noticed in the winter when you want the higher heat, but it is more likely to be seen as inadequate cooling as with heated air consistently leaking into the vent air (or conditioning air), the perceived cooling performance would be anemic.

We recently released Service Bulletin SB2X-21-05 which inspects for this valve not properly closing, and provides rigging instructions to ensure it is properly closed.

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FITT International Women's Day Luncheon

On 8 March to celebrate 101 years of International Women’s Day, eight inspiring FEIT women were sponsored by the Faculty to attend the Females in IT and Telecommunications(FITT) International Women’s Day luncheon at the beautiful Sheraton on the Park in Sydney. 

In the spirit of this year’s United Nations theme the emphasis for this event was “Connecting Girls, Inspiring Futures”. The speakers for this event were: Eva Bishop, Sr. Director, VMWare; Fiona Floyd, CIO, Suncorp; and Deborah Hadwen, CEO, Tata Consultancy Services.

The issues covered were:
Can more be done within the industry to ‘connect’ early with the next generation of female employees, managers and business owners?
To what degree does the industry champion its role models?
How can we better present the ICT industry as having an ‘inspiring future’?

The FEIT women who attended were: Anmol Gupta (BEng); Ashley Knagge (BScIT/BBus); Christine Freeburn (BEng); Jacqueline Nguyen (BIT); Jenny Nguyen (BScIT); Daisy Yuan (BEng); Kerry-Ann Chapman(BScIT); Seline Hardy (BScIT/BBus). This was a fantastic opportunity for the students to meet and network with other women working in the ICT industry.

 

We look forward to attending more FITT events in the future!

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