How much of the "workings" should we know

Duct tape, a pair of pliers, and a few tie-wraps.

Seriously, The more you know about your particular aeroplane, the better prepared you are to deal with whatever hiccup may ocur. Learn all you can.
 
That's why I enjoyed flying engineer on the 727.

"You need another 1000 psi on the the b-system? Just a sec... Ok, do it, do it now!"
 
Doug Taylor said:
Whenever I've had a full-on, "holy crap get out the POH, you work the radios and I'll work the problem", systems knowledge always saved the day.

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Thats a luxury we don't get single seat, :D

I agree, having a working knowledge of what's what definitely helps. Again, no need to know how to build it, but know the basic workings of it so you can have a clue when stuff does hit the fan.

For example in the Hog (going to the way back machine here...but as much as this was hammered into us, it was hard to forget), the Immediate Action/Boldface steps for dual engine failure were:

Throttles - OFF
APU - Start
Flight Controls - Man Reversion
Left Engine - Motor
Left Engine - Start

Now this was pretty straightforward immediate action, but there were some things you had to know a little more in-depth. First off, being single seat, there's no time to break out a checklist, there's no POH, and there's no one but you. So knowing some of the systems knowledge and using it, will actually cover many of the follow-on items after the immediate action items are completed, without having to reference the expanded checklist. With this emergency, one had to know that the APU, once started, has an APU generator switch that powers backup electrical and hydraulic. The immediate actions above are all there for a reason, and systems knowledge insures you know why. Throttles go to off versus idle, since at idle, the engine will attempt to auto-start on it's own.....not good if you have temps above 200 and need to motor them down first, or you'll have an overtemp. APU start provides air only in order to be able to begin motoring. Going Man Reversion gives you some flight control ability. Motoring and then start of the Left engine gets you going again systems-wise. IF the left won't start and you go to start the right, you have to know that the APU Generator has to be switched on first in order to get the electric boost pumps going if starting with the right engine instead of the left first. Once you get an engine started and hydro going, immediately get out of man reversion and into normal flight controls again. Both of these aren't on the immediate action checklist items, but knowing the basic system workings makes these into now-"common sense" items that you just know to take care of; and when you have a chance to get into the expanded checklist, you'll note that you've already taken care of them.

This is just an example of how knowing systems at a working level will really help you. Do I know how to build the electrical/pneumatic/hydro systems on that plane? No. But I also don't need to. Pilot knowledge is one thing, FE knowledge is another. Also, as an aside, its a testament to the disciplined training the military gives in regards to systems knowledge and EPs, as I haven't flown a Hog in 5 years, yet I still remember the immediate actions and "why's" behind them, systems-wise, as if it were yesterday.

On a similar topic: Doug, at your airline when you were on the 727, did you personally notice a difference between the systems knowledge levels of the Second Officers (pilots that were riding the FE panel) and the Professional FEs who weren't pilots? IE- did the PFEs seem to have a more in-depth knowledge, and if so, was it simply because that's all they did?
 
The PFE's were mechanics AND FE's and when I did my IOE on the 727 panel, I had what they called a "Yellowbird PFE"... which meant that he came from National. Most of the National guys were, at the time, running the training department so I had to know parts, pieces, the whole "I'm an electron" game and I think it worked pretty well for the most part.

I'm of the school of thought that the more "magic" the aircraft does, the less you have to know, but the more you SHOULD know. Here's an example. We hopped into a 757 a few days ago and during pre-flight, some dork had depressed one of the "Cargo Fire" switches which arms the bottles.

I tried to deselect the switch but it didn't work so I just 'popped' it pretty hard (like Fonzi!) and it was de-selected.

At that point, we had a lot of other systems failures and we really couldn't figure out why the "trim air" was showing inop. So, using systems knowledge that I got from just reading maintenance manuals and gouge from the 'old' training program where we had to 'build the airplane/I'm an electron" I remembered that when you arm the bottles, a whole litanny of things happen and it was probably a reset in the E&E compartment that would probably reset the BITE and reset the trim air logic.

Saved probably an hour of troubleshooting by just knowing how to talk to the mechanic.

There are too many guys that will write something up, figure it'll be an hour and disappear to Starbucks.
 
I am in the learn as much as you possibly can camp. I spent a good chunk of my pro flying career working days in the shop as a grunt along side the mechanics. There is absolutely no disputing the fact that this experience made me a much safer pilot. Not because I learned how things work so much as because I also learned how they fail. A book can teach you how the systems work. Working in a shop will teach you how they work as well as showing you how and why they fail.

I am not saying this is something that every pilot should do. But I am definitely saying it is something any pilot ought to do if given the opportunity. I learned to spot things from those mechanics that some 30 year pro pilots I've flown would skip right over.

I know pilots who simply toss the keys to their mechanic on whatever schedule they feel is appropriate and have zero interest in ever seeing any part of the plane besides the view from the front left seat. And that's fine for them, I don't fault them for it. But I'd be lying if I said I wasn't more hesitant to jump in their plane with them than I am with a pilot who is skilled enough to assist the mechanic during the annual and takes the opportunity to do so. Being that hands on makes for a better maintained aircraft in every case that I've personally seen. Of course I'm talking strictly part 91 piston ops here, part 121/135 or turboprop/bizjets are a whole different kettle of fish.
 
Over the years I've found it definitely helps to be knowledgeable about certain systems. I think it was Chuck Yeager who once wrote that a pilot should learn as much about his/her airplane as possible. I usually have my students get to the point where they can diagram certain systems- electrical, fuel, hydraulic. Why? These systems will bite you in the butt if you don't understand them and being able to draw a simple block diagram demonstrates that you do understand them. I'm not looking for perfection or artistic flair and I'm not talking about knowing what system is hooked up to what bus (although you might want to know this about some systems), but in a system with 15 busses you might want to know how it is outlined and what generators/alternators/inverters supply what bus. Same with fuel systems. I've seen too many fuel systems that can eat your lunch and there are too many accidents caused by pilots not understanding their fuel system- fuel is in the airplane, it just is not getting to the engines because the pilot does not understand the fuel system. Even a simple 172 fuel system can cause problems if a pilot does not understand it, and I've seen too many pilots "checked out" in 172s who don't understand it (don't put the fuel selector on left/right on shutdown, don't understand why the left tank burns down faster than the right tank, don't understand why you need vented fuel caps on EACH tank).
 
I think the big important difference here is working knowledge of systems verses intimate knowledge of them. I firmly believe that a working knowledge IS required, however, as in Mike's example above, we don't need to know how the missiles locks on and tracks, we just need to know how to make it kill a T-71.

The building block Idea has merit I think. Since us small plane pilots will hopefuly at some point be flying larger complex airplanes, it is good to get a grounding in systems. However, there are plenty of people who will have no desire to fly anything more complicated than a 210. So for them what is the higher level we are building upon?

Now I grant that a transport category class aircraft has systems that are lightyears ahead of a 172 when it comes to choices in configuring them. Just look at the number of switches in a 737 compared to a cessna 172. In that case yes a deeper understanding of how AND what is needed. In addition you also have the MEANS to troubleshoot to attain what is needed.

What is Configurable in a 172? Mixture, Flaps, fuel selector, and battery? There is not a whole lot I can do in the event of in flight critical situation with systems. I admit that there are a number them that do exist, but I can't think of one that requires more than a working knowledge of systems.

Again my prop Governor example. Give me a situation in flight that knowing what a speeder spring does is more than simply trivial.
 
poser765 said:
The building block Idea has merit I think. Since us small plane pilots will hopefuly at some point be flying larger complex airplanes, it is good to get a grounding in systems. However, there are plenty of people who will have no desire to fly anything more complicated than a 210. So for them what is the higher level we are building upon?
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Well, if they are an owner-operator, they can know if a shop is BSing them or not. Or they can give a more accurate description for the shop to chase a problem, if they can discern between a short in a wiring harness, or an actual intermittent problem, IMO.

Now I grant that a transport category class aircraft has systems that are lightyears ahead of a 172 when it comes to choices in configuring them. Just look at the number of switches in a 737 compared to a cessna 172. In that case yes a deeper understanding of how AND what is needed. In addition you also have the MEANS to troubleshoot to attain what is needed.

What is Configurable in a 172? Mixture, Flaps, fuel selector, and battery? There is not a whole lot I can do in the event of in flight critical situation with systems. I admit that there are a number them that do exist, but I can't think of one that requires more than a working knowledge of systems.

Again my prop Governor example. Give me a situation in flight that knowing what a speeder spring does is more than simply trivial.
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This may or may not answer your question.

I know in the 747-200, I use this as it was an old technology plane, as were the 172s I flew, the only means you had to know were some lights and gauges. No help trouble shooting from the airplane, just systems knowledge.

Let's say you have an oil pressure light and an oil pressure gauge. When they disagree what are you going to do? Obviously with 4 engines, we could shut one down and not give a rat's ass. In a single, it's a critical ballgame. Do you need to land in the field you're over, or can you fly another 15 minutes and land at the 5000' foot strip that happens to have a Cessna service center?

The only thing I wish I did when I was young was to get the A&P.....
 
Polar, I agree with you completely. I can see the benefit of an owner knowing the details, and think i is awesome if you have the means to get an A&P. That's just good sense. Where I work i am pretty sure the wrench turners would come running and screaming if the pilots went after an airplane with a screwdriver.

Your Second example is full of merit as well. Every pilot should know how to handle that situation and what it means. However, I don't see the point in knowing that the oil temp probe is a dilythium cathode box housed in the left filange and routed through the flux capacitor.
 
poser765 said:
I think the big important difference here is working knowledge of systems verses intimate knowledge of them. I firmly believe that a working knowledge IS required, however, as in Mike's example above, we don't need to know how the missiles locks on and tracks, we just need to know how to make it kill a T-71.

The building block Idea has merit I think. Since us small plane pilots will hopefuly at some point be flying larger complex airplanes, it is good to get a grounding in systems. However, there are plenty of people who will have no desire to fly anything more complicated than a 210. So for them what is the higher level we are building upon?

Now I grant that a transport category class aircraft has systems that are lightyears ahead of a 172 when it comes to choices in configuring them. Just look at the number of switches in a 737 compared to a cessna 172. In that case yes a deeper understanding of how AND what is needed. In addition you also have the MEANS to troubleshoot to attain what is needed.

What is Configurable in a 172? Mixture, Flaps, fuel selector, and battery? There is not a whole lot I can do in the event of in flight critical situation with systems. I admit that there are a number them that do exist, but I can't think of one that requires more than a working knowledge of systems.

Again my prop Governor example. Give me a situation in flight that knowing what a speeder spring does is more than simply trivial.
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Part of the problem I have seen both personally and in accident summaries is where pilots do not really know their simple systems and it gets them into trouble. Some have given examples of fuel system problems- I've seen this with the 310 where it is easy to wind up with less fuel than planned if you do not understand the fuel system (unused fuel from the engine is sent to the main tank- and if the main tank is full it is vented overboard). Lack of knowledge of electrical systems has brought more than one airplane down. Do you REALLY want to keep resetting that CB? Do you REALLY want to take off with a dead battery in an airplane with FADECs? How many busses does the airplane have, and what will happen with load shedding? Not something you want to pull out the AFM and start reading about while IMC.
 
poser765 said:
Polar, I agree with you completely. I can see the benefit of an owner knowing the details, and think i is awesome if you have the means to get an A&P. That's just good sense. Where I work i am pretty sure the wrench turners would come running and screaming if the pilots went after an airplane with a screwdriver.

Your Second example is full of merit as well. Every pilot should know how to handle that situation and what it means. However, I don't see the point in knowing that the oil temp probe is a dilythium cathode box housed in the left filange and routed through the flux capacitor.
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I think the idea is to over learn.

Then you forget that the oil temp probe is a dilythium cathode box housed in the left filange and routed through the flux capacitor, but you remember that the oil pressure gauge and the light have different power sources. The gauge is showing Zero (DC dies), but the light isn't on. You do a light test and it comes on. From that you remember that testing the oil pressure light actually sends a simulated low pressure signal proving the light, and it's circuitry, is operating normally.

I used to wash airplanes in the MX hangar in college. They'd let us come over to planes they were working on, take and poke stuff with a sharp stick and ask questions.

You'll come to realize mechanics like talking about fixing stuff like pilots like to talk about flying.

And you build a relationship with the guys that keep your ass safe in the air, as well as gain knowledge that might come in handy somewhere.
 
Ok ok...Mayhaps you have swayed me with your eloquent prose.

EDIT to save face. Just for the record I am in no way abdicating not teaching systems as they relate operationally to a pilot. Just questioning where opperationaly ends and theory begins.
 
There are people out there who still think that if you turn the master off the engine will die.

You're flying along in a Piper Arrow at 7500 feet all leaned out and singing sweetly when all of a sudden the engine begins to shake like crazy. You scan the gauges and note the oil temp looks fine as does oil pressure, manifold pressure has gone up minutely, RPM is the same, the EGT needle is on the zero peg, fuel flow reads 14gph, fuel pressure looks good but you turn the pump on anyway just to be sure.

What problem do you have? How do you deal with it?
 
Mixture Rich, relean, and carb heat maybe if plane has it. Other than that what else can be done?

Of course maybe I'm an idiot. Please enlighten me.
 
trafficinsight said:
There are people out there who still think that if you turn the master off the engine will die.

You're flying along in a Piper Arrow at 7500 feet all leaned out and singing sweetly when all of a sudden the engine begins to shake like crazy. You scan the gauges and note the oil temp looks fine as does oil pressure, manifold pressure has gone up minutely, RPM is the same, the EGT needle is on the zero peg, fuel flow reads 14gph, fuel pressure looks good but you turn the pump on anyway just to be sure.

What problem do you have? How do you deal with it?
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Plugged injector on the cylinder with the one EGT probe?
P.S. a 4-point CHT+EGT is really really nice to have.
 
trafficinsight said:
There you go, what clued you into that?
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Shaking and the zero EGT reading make it sound like one cylinder isn't firing. The fuel flow measurement AFTER leaning is way too high for an IO-360, and a blocked injector would back up the pressure in the fuel spider enough to cause that reading.

The slight rise in MP puzzled me at first, but I guess with one cylinder not firing, the airflow through the engine would be just slightly slower, increasing the manifold pressure just a touch.

P.S. I'm an A&P ;)
 
What button can you push to resolve this situation in the cockpit?
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The mixture knob, full rich. Then if the engine smooths out land at your leisure, tell a mechanic you believe have a plugged injector, probably the number 1 cylinder since that's where the EGT probe is, go grab some lunch and come back to continue the flight.

OR...

Declare an emergency, land at that uncontrolled virtually abandoned field below you because "the engine is coming apart." Call the flight school and tell them that you refuse to fly the airplane due to their shoddy maintenance. Rent a car and drive home cursing the entire way.

actually... now that I think about it, I'd prefer the second option since it means I'll get more flight time going out to rescue the airplane on your dime!

Knowing a little bit about systems, in this case, saves you money ;).
 
Roger said:
Shaking and the zero EGT reading make it sound like one cylinder isn't firing. The fuel flow measurement AFTER leaning is way too high for an IO-360, and a blocked injector would back up the pressure in the fuel spider enough to cause that reading.

The slight rise in MP puzzled me at first, but I guess with one cylinder not firing, the airflow through the engine would be just slightly slower, increasing the manifold pressure just a touch.

P.S. I'm an A&P ;)
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Then you cheated haha!

Yeah, so in this case being a smart pilot you know that the fuel controller meters fuel based on the fixed size of the injector orifices, and that the flow gauge is actually a pressure gauge but it's marked in gallons per hour, when the injector plugged all of a sudden the orifice got smaller and the pressure in the flow divider increased, which gave you a high, and inaccurate, fuel flow indication.

pushing the mixture rich will often overcome the blockage enough to get that cylinder back with you, at which point, although I don't recommend flying cross country with a plugged injector, flying to a convenient airport with maintenance services is no big deal.

The EGT indication just gave away which cylinder had the problem... and I'm with you, those graphic EGT/CHT gauges are the bees knees.

Just as an aside, does anyone else here take note of what manifold pressure gives you what RPM in the runup so that you know you have a fouled plug before you even do a mag check? ;)
 
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