Friday, August 8, 2014

War Stories - Episode 22: L'il Abner's got nothing on me!

L'il Abner was carried by the Philadelphia Evening Bulletin when I was a kid.  It was getting a bit long in the tooth by the time I started reading it, but it left a few lasting impressions.  Pretty much everyone knows about Sadie Hawkins Day.   Even my kids know, even if they don't know its origins.  L'il Abner's mother, Mammy Yokum used to say, "Good is better than evil because it's nicer".  Almost theological...

L'il Abner himself was employed as a mattress tester.

For a day, so was I.

After Stanley Crane came aboard as CEO, he began building up the business car fleet, making it easier for management to get out on the road and actually see and feel the railroad.  Conrail purchased some, older, cheaper equipment and then overhauled or rebuilt it at Reading Shops.  One of them was an old Southern Coach that was converted into a bedroom car in 1984 and numbered CR8.

In 1985, it was retrucked from six wheel trucks to four wheel ones.   To make sure that the new suspension gave a good ride, we did some ride quality.

At that time, I was one of the experts at Conrail for performing ride quality testing.  Normally, this involved mounting seismic accelerometers over the bolster centers and running cables to a massive, 80 pound chart recorder that was equipped with low-pass filtering.  You want to measure vibrations in the range of the natural frequency of the suspension laterally and vertically, typically in the <5 Hz range.

Fortunately, I had become acquainted with the Ed Lombardi at Amtrak who worked at and later ran their test department.  They had a couple of handy devices that helped to make this job a bit easier.  One was a Japanese two axis accelerometer - strictly mechanical - that had the right low frequency pass filtering built in.  If I remember right, it even had a wind-up clock motor drive for the chart recorder.  It was a brilliant little piece of mechanical engineering!

The test involved measuring the lateral and vertical accelerations and recording them on a chart.  Later, I'd analyze the chart looking for highest peaks per mile and number above a threshold per mile.  It allowed a measure of how well the suspension isolated track inputs.

Amtrak also had an electronic human vibration exposure meter designed to provide a frequency weighted measure according to an international standard (that I have forgotten...)  It came with a seat cushion accelerometer - that looked a great deal like a "whoopee" cushion - designed for measuring passenger comfort.  This was a more sophisiticated way of determining passenger comfort but not as easy to understand the relationship between accelerometer input and meter output.

I borrowed both from Amtrak, making a quick round trip to DC on Metroliner Service trains to pick them up.  A hard day's work!  Being curious about both, I gave them a quick workout during my train ride and later driving to Reading.  It also gave me some basis of comparison for the results from testing passenger car.

We had established a nice test route for these business car trips.  We'd head out of Reading, down to Philadelphia, wye at West Falls and then back onto the connector from West Falls to Zoo tower.  From there, we'd head west on Amtrak to Harrisburg.  There were some nice stretches of 90 mph running as well as a nice mix of welded and jointed rail on Amtrak's Harrisburg Line.  We'd wye at Harrisburg, then head back to Reading.

I drove to Reading early on Tuesday, July 16, 1985 to do the testing. We had a locomotive, CR 8 and an open-end platform business car in the consist - Car 14?  Car 10 Car 4? Not sure which.   The bolster centers were in the middle of the bedrooms, as I recall.  I set up the accelerometer and got ready to manually annotate the chart with milepost data as the train moved along.

I got set up and the train headed for Philadelphia.  We wyed and headed for Harrisburg.  About this time, one of the suprevisors from Reading shops mentioned that they had purchased both soft and firm mattresses and wondered if there was a difference in comfort while the train is moving.

I can do this!

I lie down on one mattress and put the whoopee cushion under the small of my back, fire the meter up and give it 5 minutes.  Then I move to the other room and repeat.

Bottom line?  No discernable difference.

The four axle trucks?  Nice ride!  Well sprung and damped.  Nothing dangerous.

I had all the data I needed by the time we reached Harrisburg so I enjoyed the trip back to Reading at 50 mph from the open rear platform of the business car.

Lying down on the job?  Yep. Mattress testing! Just like L'il Abner!...and riding on the rear platform of an observation car on a nice sunny, warm summer day. Tough work, when you can get it!

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