How is this even possible?

[n3437d]

Someone please explain this to me? It appears its much harder to start a 170 than a commercial twin engine jet

http://www.switched.com/2008/07/23/airp ... 1200325963

[GAHorn]

I'll make a prediction: Improper use of checklists. Improper training of mx personnel. Improper supervision.
The "mechanic" was attempting to perform a compressor wash and thought she was merely rotating the engine by pushing a starter switch... but instead of using a "Engine motoring checklist", she had actually used the "Engine Start" checklist which included introducing fuel for an engine start, ... coupled with a thrust lever improperly placed at high power.
The work was in front of an open hangar which had two other regional jets inside, and the subject airplane started and ran into the hangar striking the other two aircraft. I last heard that two of the aircraft will be a total loss.
This is an old story, not exactly "news".

[Bruce Fenstermacher]

Yes in many cases a recip airplane or helicopter is harder to start and fly than a turbine powered one. Now I'm not talking about proper procedures. Just that recip engines can be a real pain to start. Turbines on the other hand generally start when activated and fuel is introduced.

With the new FADAC systems in the simplest of terms it would be a matter of flipping the fuel switch and then flipping the start switch. The engine starts itself.

[GAHorn]

Yes, I agree, and irionically, ... when FADEC was introduced it was praised as making engine starts "idiot proof" and would prevent starting accidents (such as overtemped starts, failed starts, etc. etc.).

[c170b53]

I love this kind of stuff because it happens all the time. You just don't hear about it because its not in the "Industry's best interest". As in any profession it takes time to acquire skills to do a complex job. Training is or was a large part of the process to enable mechanics to safely carry out their duties. Problem is no one wants to pay for it in the airline environment today. I've given up trying to enlighten folks, now I just sit back and giggle. I'm hoping of course that nobody gets hurt but the odds are someone will. The business is definitely at rock bottom.

[GAHorn]

You're absolutely correct, Jim!
When the finances get "tight" ... they'll keep those highly paid execs ( as if the monetary losses can be stopped by keeping the same guys who caused it)... and cut back on "expenses" like training. The irony is, if they'd spend the money on training ... that's where serious losses can be alleviated.

The most important person at General Motors is not the CEO in the executive office bldg. It's the person out there on the assembly line who's building MY car! The most important person at the school house is NOT the principal, or the administrator down at the administration bldg. It's the TEACHER who is molding those little lives and providing the actual education. Get rid of all the Wall Street whiz-greedys in airline management and let the people who actually know how to fly, maintain, and serve customers and airlines will make a turn-around. Train pilots to pull back on the throttles after Vfto and watch those Fuel Flows drastically drop... until a clearance on-course and to cruise altititude occurs, and airlines will see huge savings. (It makes no sense to go fast the wrong direction at low altitude.*) That takes TRAINING!

Similar training can have similar effects in maintenance dept's. But training is where they'll cut, you watch and see.

* I recall making an impressive demonstration of that back in the mid 80's, when my flight department operated two identical Viper-powered Hawkers. We had a couple weeks of business meetings in Miami and Brownsville. Invariably we'd take off on either 8L or 8R, one just before the other. The difference was that I'd not briefed the other pilot on technique because I didn't want to appear to be micro-managing his cockpit. My own technique had been taught to me by Beryl Minard, a very experienced old guy with about 5,000 hrs in type.
Immediately upon getting the gear up, air valves on, and t.o flaps retracted I'd pull the thrust levers WAY back to barely maintain Vfto (minimum speed for flap up after takeoff.) It would reduce the fuel flows from 7800 lbs/hr to 2400 lbs/hr. I was pointed East out over the Atlantic and MIA departure invariably would take us out about 10 miles before a turn south for about 10 miles then a turn west and a clearance on-course/to-altitude. That's when I'd power-up for normal climb, which was 250 kts and 98% power (about 7400 lbs/hr, which would diminish with altitude.) By the time I"d reached FL240 the fuel flows would be back to 3,000/hr and the TAS would be up to 350 kts and climbing. FL 350 was reached in about 35 mins after liftoff, and the TAS would be just over 420 kts. By the time I reached Brownsville, TX I was landing with 1600 lbs of fuel (45 mins), but the other crew had made a fuel stop at New Orleans and would arrive two hours later.
We did this twice before the other crew tried it the "Minard Method" and made it non-stop KMIA-KBRO. Training made a huge difference, and saved hundreds of gallons each trip. At todays prices of $5-$8 / gal for Jet-A , that would really add up.

[AR Dave]

When aircraft engines are washed by mechanics, isn't it called waterwashing the turbines? And isn't the engine running, at least spooled up, while being washed? That's my observation when our mechanics waterwash my turbines here at work.

[GAHorn]

I"ll bet you are talking about compressor turbines on a pipeline?
Most aircraft engines have a procedure for a "compressor wash" that clean the compressor turbine blades of built-up dirt that reduces efficiency. The only procedure I've witnessed has been one which gently sprays a cleaning solution (soap) into the compressor section, allows it to sit/soak for a predetermined time, and then the engine motored, and then cleared of solution with water. After the procedure is completed, it's taken out to the run-up pad and actually started, mostly to record results and dry the engine. Nothing is ever sprayed into it while it is running.

I've heard anecdotes of helicopters getting a short blast of crushed walnut shells while idling to aggressively clean dirt/mud off the compressors from operating in dusty conditions, but I thought that was an emergency manuever in Viet Nam.

[AR Dave]

They're LM2500's which hung on L1011 Aircraft - is that Lockheed Martin?
The Waterwash Cycle is ran at a lesser rpm (guess about like starter speed) the water and soap are sprayed into the intake and wash debris through each stage. Then we shut em down and look at the blades with a Boroscope. Why is it neccessary to gently spray aircraft turbine blades during mainteance, when they routinely go through rain storms?

Just took this picture for you George - they are soo loud, I have to squeeze between them and the wall every 6 hrs.

[voorheesh]

We used to use a product called "Turko" (sp?) to clean compressor blades on our twin otters and shorts 330s pt6s in the 1970s and 80s. Turko was basically ground up walnut shells that would have a light abrasive affect. We also used to do a power recovery wash using distilled h2o. As I recall, enviornment such as salt air and high pollution would dictate the type of wash needed and trend monitoring would tell you when to do it. O300s are a whole lot easier to keep running.

[c170b53]

There's lots of "wash" techniques. Some use a detergent some just water. The engines are static during the wash or in some cases where the wands are held rigid in the inlet the engine will be motored. On the west coast you got to wonder why. The most effective " wash " is coking where an abrasive grit (ground up coke powder) is sprayed into the inlet at flight idle. At night its a small light show. The wash is often done to try to maintain the egt margin.

[170C]

I have heard that back in the 1960's the Navy folks would get build-up on the turbine blades of the Allison turbo prop engines on P-3's and they would toss (?) walnut shells into the intakes to clean them. I don't know if this was an approved method or some unofficial operation.

[voorheesh]

Check it out: http://www.dennisdawson.com/walnut.htm Also Turko was a misspelling. The real product is "Turco" an alcohol based cleaning solution for gas turbine compressors (not walnut shells).

[GAHorn]

"Turco" is a brand name. They make many different types of chemicals, for aviation, as well as for other industries. They make chemical paint strippers, cleaning agents, etc., etc.,. "Turco" is a tradename of products made by Telford Industries.
I remember using "Turco" paint stripper back in the early '70's to strip a Mooney in trade for flying time. That stuff would really burn the skin if you got it on you. But it'd strip anything including multiple coats of paint.

http://www.telfordindustries.com.au/pro ... ductID=154