King Air C-90

All at a cost, and not likely to perfection.

This is not a perfect world. Expecting perfection is a fools errand.

Who said anything of perfection, but you?
You are lucky, maybe flown some new equipment, but as KAs age they become more and more difficult to match rigging. And it is no 2 hour job, as Henning suggests. Sure, you can slam a rental engine on in a few hours with a couple of guys. And then you can spend the next two days rigging, if you like perfection. And even then, they are likely to just be close in one direction.

I've flown new equipment, and very old equipment, and was a Director of Maintenance and Check Airman for both, in a King Air operation. Having done the job, I don't agree with you a bit. There is no more difficulty rigging an older King Air vs. a newer one, regardless of time or cycles. It's not exactly rocket science. Again, no one has said anything about perfection, but you.

Proper maintenance and rigging isn't a miracle, and isn't uncommon. You appear to have consigned yourself to flying poorly maintained equipment.

It is very easy to hurt a PT-6, especially when you are rigging it. They don't like to be started over and over again in a short period. One should, if possible, wait 30 minutes after shutdown for a restart. Rigging requires multiple restarts.

You don't appear to have much experience with King Air's or PT6 powerplants. Are you not familiar with max motoring practices, as well as cooldown practices? So long as engine temperatures aren't exceeded, there's no reason not to restart the motor, and there's no great difficulty in rigging the engine. There really isn't. You seem to believe it's a holy practice that needs a priest. It isn't. The rigging practice is spelled out very clearly in the aircraft and pratt maintenance documents. Keeping it in rig isn't complicated, and age of the aircraft has nothing to do with the matter.

I don't know anyone, personally, who has ever damaged an engine as a function of rigging the engine. Have you done so?

You clearly speak from experience here.

Yes, I do. From small pistons to the largest radials, both operating them and maintaining them, as well as most types of turbopropeller and turbine engines.

I've seen piston engines damaged almost every way you can imagine, from failure to put oil in engines to running them rich and running them lean, from propeller strikes to lifted heads to blown and failed turbos and PRT and superchargers to sucked valve and badly timed mags. It's easy to hurt a piston engine; there's not a lot one can do operationally to hurt a PT-6.

The equipment I flew was maintained by large "Beech" shops, Flightcraft and Western Aircraft Services, and paid for owners who always paid the bill. A brand new airplane with consecutively numbered engines can be rigged pretty good. Once the airplane has been in service for a few years it becomes more difficult because the engines become mismatched. One engine might need a hot section due to FOD or just not making target power or something. Rental engine might be installed. When you go to an overhaul facility you find that there are different spec CT blades available for the same engine. These things add up over time and usually an airplane will have engines that no longer match like they did when new.

You've never actually rigged an engine, let alone a PT-6, have you? Sounds like you contracted to have someone else paid to do it, and have your understanding second hand. You're mixing unrelated details. Do you not understand blade classification? Obviously engines have different levels of efficiency, and different states of condition; this isn't exactly a revelation. This is why we rig the engines, you see. There is no reason why the engines can't be rigged properly, and the controls rigged evenly in the cockpit. This is standard, this is expected, this is normal.

Proof you've never looked out of a 200 at night. 10% of the thrust of a PT6 is jet exhaust at cruise. A beautiful blue/yellow flame is quite definitely flowing from those stacks.

I've flown 200's a great deal at night, primarily doing aeromedical operations. I've flown a lot of other PT6 powered aircraft at night, as well, and I've never seen a four foot flame coming from the PT6 at night. I really think you have no idea what you're talking about, and I don't believe for a minute you've ever seen a four foot flame coming from a PT6 exhuast at night. I've been through Flight Safety for the King Air as well as Simuflight. I've taught and instructed in the airplane, I've flown them on the line, and I've maintained them and as previously mentioned, have been a Director of Maintenance twice; once in an operation using multiple King Airs. I've never seen a four foot flame out of the exhaust stack of a King Air, and I very much doubt you have, either. If you have, and if you think that's normal, you have some serious judgement issues and have had some very seriously poor experience with poorly maintained equipment.

Furthermore, if you're flying equipment capable of producing four feet of flame out the exhaust for even a short term, you're looking at severe engine damage, burned combustor liners, and a very damaged hot section. You won't be operating the aircraft in that condition for long.

I don't know where you are coming from, but our airplanes worked for a living. If we didn't get 45 hours a month the airplanes would go away.

You really think 45 hours a month is a lot??

You understand the difference between hours and cycles, do you not?

Don't spend the bosses money on a witch hunt. It sounds like you flew for a government agency in which case money was wantonly wasted on frivolity.

I have flown for government agencies, and I've never seen the money spent on those flight operations with frivolity. I've also flown in charter operations, fractional operations, military operations, cargo operations, passenger and medical operations, atmospheric research operations, test and maintenance operations, and instructional situations and operations.

Spending money on properly maintaining the aircraft is no "witch hunt." That you believe this to be the case ends the conversation, betrays your inexperience, and speaks volumes about your judgement.

Simply put, you're unsafe. You're unsafe because you don't know the depth of your ignorance on the subject, and you're unsafe because you accept mediocre maintenance and equipment.

Given your inexperience, you may rest assured that 45 hours a month is a low use aircraft, that mismatched rigging is not the norm in King Air's or most other equipment, and that the PT6 isn't a difficult powerplant to operate, and is fairly bullet proof.

It's the only turbine engine you've ever operated, isn't it?
 
I've never seen a four foot flame out of the exhaust stack of a King Air, and I very much doubt you have, either. If you have, and if you think that's normal, you have some serious judgement issues and have had some very seriously poor experience with poorly maintained equipment.
Sadly this is the truth more often than should be. When you combine clueless lazy pilots with clueless lazy mechanics, equipment suffers. Combine that with an operator who is trying to make a quarterly bottom line and you could conceivably get 4' flames shooting out the stacks of their PT-6s:dunno:, or maybe they got afterburners for theirs which is how they got 10% thrust out of the exhaust.;)

:idea: How cool would A/Bs be for a TPE 331 plane?
 
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I've never seen four foot flames from TPE-331's, either.

I flew Piaggio Avanti's with Pratt -66's on them; they went right to FL410 and outpaced Citations, while getting the same fuel burn as a King Air 200 with a bigger and quieter cabin. Afterburning won't help on a turboprop and of course isn't necessary, but there's no reason why a turboprop can't be fast and efficient.
 
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I've never seen four foot flames from TPE-331's, either.

I flew Piaggio Avanti's with Pratt -66's on them; they went right to FL410 and outpaced Citations, while getting the same fuel burn as a King Air 200 with a bigger and quieter cabin. Afterburning won't help on a turboprop and of course isn't necessary, but there's no reason why a turboprop can't be fast and efficient.

Of course it won't, at least not more than a small fraction, but it would look cool and would produce a 4' flame.;)
All you to have to do is understand that if a turboprop gives up most of it's pressure to the prop that a 4' flame out the pipe isn't going to happen unless the engine is mortally damaged.
 
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Thanks guys. Tom Clements also responded to me on another board and agreed the fuel flow gauges shouldn't be off as mine our. Here's his post below. I've sent it on to my shop.

Dave
===================================================

Second, if your fuel flow gauges are quite inaccurate, something is wildly wrong. Those suckers are nearly perfect! If both are reading about 20 pph high, I know the problem: The start purge valves are not closing after start as they should. If it is something else, the gauges or the transducers must have problems, but the norm is nearly perfection.
 
Let me ask another question: on this plane, I am making book torque using either the C90 or the C90-1 power settings, but the left engine runs about 20 degrees hotter than the right still under the redline ITT of 695.
If I run the engines per my C90 POH, they are very cool as has been discussed. So, I ran the C90-1 torque setting on a trip back from Florida at FL220. The target torque was just over 900; the left engine made that, but near the 695 redline. The right made torque about twenty degree cooler.
What insight might that provide?
I've attached a pic running the engines at POH power settings and, as you can see, ITTs are pretty cool. The left is about twenty degrees hotter than the right. That same relationship at the C90-1 power settings exists at higher torques. The left was near 695 at FL220 on a recent trip running C90-1 torque.

Best,

Dave
 

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Let me ask another question: on this plane, I am making book torque using either the C90 or the C90-1 power settings, but the left engine runs about 20 degrees hotter than the right still under the redline ITT of 695.
If I run the engines per my C90 POH, they are very cool as has been discussed. So, I ran the C90-1 torque setting on a trip back from Florida at FL220. The target torque was just over 900; the left engine made that, but near the 695 redline. The right made torque about twenty degree cooler.
What insight might that provide?

Best,

Dave

Same extra fuel leak that Tom Clements was talking about earlier? Either that or you have lower pressure/higher clearances in your hotter temp engine.
 
Tom's response to a post I made where I described the left running 20 degrees hotter than the right but making book torque.

Dave
======================================================

Full ViewRE: C90 Training


From:"twcaz@msn.com" <twcaz@msn.com>
online


To:Dave Siciliano <dsiciliano2@sbcglobal.net>



Roger that! It is quite unusual for ITTs, N1s, and fuel flows to match perfectly when equal torques are set at equal propeller speed. It's nice when it happens, but it is the exception. To see, perhaps, a 20 degree temp split, 1.0% N1 split, and/or 15 pph fuel flow split is more the norm than the exception.
 
Tom's response to a post I made where I described the left running 20 degrees hotter than the right but making book torque.

Dave
======================================================

Full ViewRE: C90 Training


From:"twcaz@msn.com" <twcaz@msn.com>
online


To:Dave Siciliano <dsiciliano2@sbcglobal.net>



Roger that! It is quite unusual for ITTs, N1s, and fuel flows to match perfectly when equal torques are set at equal propeller speed. It's nice when it happens, but it is the exception. To see, perhaps, a 20 degree temp split, 1.0% N1 split, and/or 15 pph fuel flow split is more the norm than the exception.

It makes sense since the internal tolerances in the turbines and compressors will never be exact and change with time. Lower pressure per torque will require more fuel to do the same work and achieve a higher temp. The question becomes at what split does it become indicative of going beyond tolerances within the engine?
 
Based on the picture (as best I can see the gages) the left engine appears to be making same torque and temp as right but with ~2% more N1 and less fuel flow. Am I seeing it correctly?

When you top both sets of tanks after a trip, is the quantity difference noticeable? Which FF#/hr reading appears to be more accurate based on trip times? Based on that calculation, which gage (L vs R) do you think is more probably more accurate? What is book fuel flow for the altitude and atmospherics during the flight?

20 deg temp splits (on the gages) are fairly common with many possible causes. The obvious problem is that you don't know if the engine is actually running hotter or just indicating hotter.

Dallas airmotive overhauled the engines on BB-1245 at 3,000 hours. Prior to this first-run O/H the engine gages matched almost perfectly, but during post-overhaul test flight the temp split was ~20 deg. They said it was within limits and were initially resistent to further work. We objected, with the knowledge that even though the 20 degree split was insignificant with fresh parts and zero time, that same split could be very significant later during power runs to determine that would determine whether the engine would meet max engine performance required for continued operations.

They relented, split the engine and changed the class of guide-vane on the hot engine, even though the correct part (per the manual and as removed during the overhaul) was installed in the engine. The problem was lessened but not totally cured, so they adjusted the temp indication settings that I can't remember off-hand) and told us they had done all that they could/would do.

A side discussion at the time centered on the fact that the torque and temp indication systems were both overhauled and re-calibrated during the overhauls, and that the original engines might have been set up (rigged) to provide equal gage settings when in fact some splits would have been evident without the jiggery.

If you talk to the PT-6 guru that provides consulting services to your shop, he will give you about a dozen more scenarios that might contribute to the mis-match. I've heard many of them and usually end up better-informed but with a headache from trying to assimilate all of it. Good luck!

Let me ask another question: on this plane, I am making book torque using either the C90 or the C90-1 power settings, but the left engine runs about 20 degrees hotter than the right still under the redline ITT of 695.
If I run the engines per my C90 POH, they are very cool as has been discussed. So, I ran the C90-1 torque setting on a trip back from Florida at FL220. The target torque was just over 900; the left engine made that, but near the 695 redline. The right made torque about twenty degree cooler.
What insight might that provide?
I've attached a pic running the engines at POH power settings and, as you can see, ITTs are pretty cool. The left is about twenty degrees hotter than the right. That same relationship at the C90-1 power settings exists at higher torques. The left was near 695 at FL220 on a recent trip running C90-1 torque.

Best,

Dave
 
This wasn't the best pic to use to show actual power settings. It does show the left engine is running about 610 and the right 590 ITT with matched props of 2000 and torque of 740. Left FF gauge is 170; right is 200. Tanks usually take very close to the same mount of refill.

When I set the engines to POH power settings, I match torque and make book IAS well under redline. I can't tell on fuel flows because of the gauge err.

When I set the engines to C90-1 torgue settings, I have no FF or IAS numbers; so, I don't know if I'm making book numbers but the left ITT is about 20 degrees higher then the right--still under redline.

So, it looks to me that I'm making book numbers, just was wondering about the left being a bit hotter than the right, and the FF gauges probably need tweeking.

On my next trip the weekend of the 12th, I'll set the plane up at POH and C90-1 book numbers and take pics so I have it all documented.

Thanks,

Dave
 
This wasn't the best pic to use to show actual power settings. It does show the left engine is running about 610 and the right 590 ITT with matched props of 2000 and torque of 740. Left FF gauge is 170; right is 200. Tanks usually take very close to the same mount of refill.

Thanks,

Dave

Wait, you're saying the hotter engine is flowing LESS fuel/torque? Hmmmmm.....

That is something I'd like to hear Tom Clements take on, he sounds like he has it pretty wired; it's baffling me outside a bearing problem of some type.
 
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This all gets back to the reasons that some are hesitant to fix what ain't broke, and why the result can be the equivalent of pulling just one thread on a sweater. Some or all of the mis-match could be a non-problem simply because the engine that is thought to be weaker is in fact right on the money and the other engine just happens to be very strong. In such case there's nothing wrong with the settings or indications, the engines are simply a bit different.

I was confronted with this exact scenario during the purchase of BB-1013 in 1997. We couldn't figure out the reason for the engine split nor could we pin-point the problem in the (supposedly) weaker engine. During the pre-buy, I came across the trend sheets, engine build data and some of the test flight data while looking for something else in one of the many boxes of records.

Using that information, we determined that one engine had consistently outperformed book settings from the get-go. So instead of one engine that was weaker than book, we had one that was stronger than book. A number of factors (such as turbine wheel to duct segment clearance) can combine to cause the engine to over-perform. In this case the answer was to count our blessings and do nothing.
 
Twenty degrees on the temp is nothing. It's easily within the range of instrument/sensor error.

What needs to be matched in rigging are the cockpit controls. Each engine will function at it's own level of efficiency, and numerous factors play into that.

If you're running close to the temp limits to get your torque, then back off. You may be used to piston aircraft in which you can run book numbers, but in turbopropeller aircraft, it's a different matter. Forget the book numbers: look at your limitations and give them a healthy margin.

Temperature is the biggest threat to your tubine engine. NOT torque.

At lower altitudes, you'll be torque limited: you'll torque out before you temp out. As the aircraft climbs, however, you may find a point at which you're temp limited and can't approach torque limits (because temps peak before torques do). Watch your aircraft limitations, especially on takeoff.

The most common two places to see thermal damage to your engine are on start, and on takeoff. Reduced power takeoffs will increase your engine life in a turbine engine substantially. You have no need of running max temps in a turbine engine: don't do it.

On engine starts, forget motoring to 12 or 15% Ng before adding fuel. Max motor: motor it until you can't get any higher %Ng off the starter before adding fuel. Let it reach it's max motoring RPM and hold it for a few seconds. Then add your fuel. You'll get cooler starts, which are much better for your powerplant. The faster you can spin that motor before adding the fuel the better off you are. This created lower temps, but also prevents combustor damage, and those are temps you won't see downrange at your ITT, TIT, or EGT thermocouples. Getting max airflow through the burner means less chance of the flame contacting the burner, and less chance for damage. Max motor on start, always.

On takeoff, spool your engines and match them at an intermediate power setting before pushing the power up to your takeoff value. Don't just watch your torque; watch your temps. Use reduced thrust (reduced takeoff power) where you can. Pratts are almost bulletproof, but they're susceptible to engine temps like any other engine. Respect that.
 
Twenty degrees on the temp is nothing. It's easily within the range of instrument/sensor error.

Temperature is the biggest threat to your tubine engine. NOT torque.

Can you explain to me what normal condition/wear would create a more heat with a reduction in fuel flow for equal torque in one vs. the other? This one is still confusing the f- out of me.
 
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Many times the wool has just been pulled over the customer's eyes. How many KAs have been sold with bad engines, but their gauges indicate perfection.

It doesn't take but a few seconds to pull the gauges and twist a screw, or adjust a pot on the transducer, adjust/replace the "Liars probe" (trim stick) to make a a bad engine indicate good. This, all in less than two hours.

This works particularly good on narcissistic ("I go to FlightSafety") pilots with poor powers of observation. I can just see them swaggering in, insisting on two hour engine rigging. Only they are capable of proper maintenance, mechanics pointing and laughing!
 
I have verified this plane is making book power more than once. In the POH there is a table provided by the manufacturer that has one match torque and prop rpm adjusted for ISA at altitude. When set properly, it gives IAS and fuel flows for that setting. I've been right on IAS. Fuel flows look right but as I've said, one gauge seems to be indicating high, but over the length of a trip, fuel consumption is in line with book. I'm well under red line at POH torque settings.

When I run C90-1 power settings, I still am under redline, but much closer. I don't have IAS and FF for those torque settings. If torque gauges would have been tampered with, I wouldn't make the other book settings.

Best,

Dave
 
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Did you verify N1 at C90-1 setting? Was either engine close to the 101.5% max? The POH doesn't show N1 or temp, although both limitations are presumed to be met. One of the engines on our family B-200 (BB-864)would make power and temps easily but N1 speed would/could creep over the limits in some conditions.

I have verified this plane is making book power more than once. In the POH there is a table provided by the manufacturer that has one match torque and prop rpm adjusted for ISA at altitude. When set properly, it gives IAS and fuel flows for that setting. I've been right on IAS. Fuel flows look right but as I've said, one gauge seems to be indicating high, but over the length of a trip, fuel consumption is in line with book. I'm well under red line at POH torque settings.

When I run C90-1 power settings, I still am under redline, but much closer. I don't have IAS and FF for those torque settings. If torque gauges would have been tampered with, I wouldn't make the other book settings.

Best,

Dave
 
Wayne: I did look at N1 and it was under 100 at the C90-1 power settings. Didn't write those down and don't recall the specifics, but seemed in the 97 range. Next trip, I'll document all that.

I have documented settings several times at POH settings. N1 was down about 91% at those settings.

Best,

Dave
 
Flew to Wisconsin today with a friend and we took all the power settings at FL230. We were right on book settings verified by TAS and FF. We also determined the left FF gauge is very close to what we are using.
We also ran the C90-1 power setting and the left engine just made torque very close to redline TIT, but it did make it. I've got a bunch of number and a pic at each setting I'll try to post with our target numbers.

Best,

Dave
 
Flew to Wisconsin today with a friend and we took all the power settings at FL230. We were right on book settings verified by TAS and FF. We also determined the left FF gauge is very close to what we are using.
We also ran the C90-1 power setting and the left engine just made torque very close to redline TIT, but it did make it. I've got a bunch of number and a pic at each setting I'll try to post with our target numbers.

Best,

Dave

What was your highest TAS and at what altitude?
 
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About 230 at FL 230 when fuel was full. As we used fuel, we gained a few knots. A bit hotter than a standard day today. I've done 235 at that altitude. But, right in that range is pretty normal.

Here's a pic of the panel at that altitude and at the C90-1 power setting.

Best,


Dave
 

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The higher fuel flow and lower temp for same torque is still confusing me.
 
After checking actual fuel burn against the FF meters, the left is pretty accurate. The right is showing about 30 PPH high. That's one of the things we were able to shake out during this flight.
We're still fine tuning several things on this plane. Adjusted Sky Watch to not work when the gear is down: we were constantly getting traffic alerts on final from folks on the ground with transponders on. It's why we put ours on standby as we roll off the runway, but most folks don't. TAWS was also very loud.

We're still talking to Tom Clemments, our folks and the PT-6 folks we know about the power settings we should run. C90 POH setting are clearly too low. We do make all book settings to confirm torque meters seem correct (TAS and FF on the left gauge seem right on). Obviously, the C90-1 target torque setting is a bit high for the left engine. We may need to back that off a bit. We make torque, but temp is near redline of 695.

Best,

Dave
 
After checking actual fuel burn against the FF meters, the left is pretty accurate. The right is showing about 30 PPH high. That's one of the things we were able to shake out during this flight.
We're still fine tuning several things on this plane. Adjusted Sky Watch to not work when the gear is down: we were constantly getting traffic alerts on final from folks on the ground with transponders on. It's why we put ours on standby as we roll off the runway, but most folks don't. TAWS was also very loud.

We're still talking to Tom Clemments, our folks and the PT-6 folks we know about the power settings we should run. C90 POH setting are clearly too low. We do make all book settings to confirm torque meters seem correct (TAS and FF on the left gauge seem right on). Obviously, the C90-1 target torque setting is a bit high for the left engine. We may need to back that off a bit. We make torque, but temp is near redline of 695.

Best,

Dave
This may be why:
AIM 2/12 version section 4-1-20. Transponder Operation
(a)(3)
Civil and military transponders should be turned to the “on" or normal altitude reporting position prior to moving on the airport surface to ensure the aircraft is visible to ATC surveillance systems. IN ALL CASES, WHILE IN CONTROLLED AIRSPACE EACH PILOT OPERATING AN AIRCRAFT EQUIPPED WITH AN OPERABLE ATC TRANSPONDER MAINTAINED IN ACCORDANCE WITH 14 CFR SECTION 91.413 MUST OPERATE THE TRANSPONDER, INCLUDING MODE C IF INSTALLED, ON THE APPROPRIATE CODE OR AS ASSIGNED BY ATC. IN CLASS G AIRSPACE, THE TRANSPONDER SHOULD BE OPERATING WHILE AIRBORNE UNLESS OTHERWISE REQUESTED BY ATC.
And this is even changed from the 10/11 revision 3!
 
Thanks Grant; I'll look at that when I get home. Many airports are still advising folks not to do that. Seems to bugger up some systems. For those of us with active traffic systems, it's a real annoyance to keep getting traffic alerts from ground traffic when on short final or right after we raise the gear on departure. At least one DE hear is giving contrary advise. I'll point that out to him once I look at it.

Dave
 
It seems to be a matter of preference. I've had Flight Check aircraft thank me for having my transponder on while on the ground, because it let them know that some bug smasher was running while they were doing low passes in the Lear 60 at close to 200 kts.

Glad you're enjoying the plane, Dave!
 
Airports with ground radar, eg KMDW, state on their AWOS to have transponders on for ground ops.
 
Thanks Grant; I'll look at that when I get home. Many airports are still advising folks not to do that. Seems to bugger up some systems. For those of us with active traffic systems, it's a real annoyance to keep getting traffic alerts from ground traffic when on short final or right after we raise the gear on departure. At least one DE hear is giving contrary advise. I'll point that out to him once I look at it.

Dave

14 CFR 91.215 says leave it on unless instructed otherwise in all controlled airspace.

"(c) Transponder-on operation. While in the airspace as specified in paragraph (b) of this section or in all controlled airspace, each person operating an aircraft equipped with an operable ATC transponder maintained in accordance with §91.413 of this part shall operate the transponder, including Mode C equipment if installed, and shall reply on the appropriate code or as assigned by ATC."

Nuisance alerts does sound like a problem, but unless ATC tells someone to shut it off... to steal a phrase...

"It's not just an adventure, it's the law!" :)

Of course it says "airspace". One could get into the semantics of whether or not controlled airspace extends to the surface. It does, by strict definition, so...?

Doing a text search of the entire FAR/AIM there's a number of systems where ATC does want them on when on the ground also. So ... Some Catch-22 built in. Rarely are those systems charted anywhere a VFR pilot can find them. Often not listed in the A/FD either.

Piles of acronyms for the different systems, no one simple chart symbol that says "transponder on, on the ground, at this airport". That could be done to alleviate confusion. See the symbol, leave it on. No symbol, shut it off. Amend 91.215 to match.
 
Nuisance alerts does sound like a problem,

They do get to be a pain, no question. When flying into busy airports where everyone has their transponders on, there are lots of warnings of "traffic..." which gets distracting when you're on final and the offending airplane is behind the hold short line.

Personally, I see more benefits than problems. No system is perfect, but they can be a real pain.
 
We're still fine tuning several things on this plane. Adjusted Sky Watch to not work when the gear is down: we were constantly getting traffic alerts on final from folks on the ground with transponders on. It's why we put ours on standby as we roll off the runway, but most folks don't. TAWS was also very loud.

TAWS (and enhanced ground proximity warning) is supposed to be loud. Hitting the ground is much louder.

Transponder use on the surface varies with the airport. Some fields require it, some don't. Usually you'll find it described on the airport information page, if you're using Jepps. You'll also hear a requirement broadcast on ATIS in most cases.

Generally speaking, you should not operate your transponder on the ground unless asked to do so. TCAS-equipped aircraft shouldn't respond with resolutions to aircraft on the surface. Other systems, however, may not have that same ability .

Disabling your traffic alert or response capabilities simply because your gear is down isn't a good idea. Your opportunities to trade paint increase exponentially as you approach the airport: coincidentaly this is also the time you'll be extending your gear. Almost every TCAS alert or resolution advisory that I've experienced has been near an airport. Not all, but most. That's a time to have the TCAS or other traffic system on and working.
 
TAWS (and enhanced ground proximity warning) is supposed to be loud. Hitting the ground is much louder.

Transponder use on the surface varies with the airport. Some fields require it, some don't. Usually you'll find it described on the airport information page, if you're using Jepps. You'll also hear a requirement broadcast on ATIS in most cases.

Generally speaking, you should not operate your transponder on the ground unless asked to do so. TCAS-equipped aircraft shouldn't respond with resolutions to aircraft on the surface. Other systems, however, may not have that same ability .

Disabling your traffic alert or response capabilities simply because your gear is down isn't a good idea. Your opportunities to trade paint increase exponentially as you approach the airport: coincidentaly this is also the time you'll be extending your gear. Almost every TCAS alert or resolution advisory that I've experienced has been near an airport. Not all, but most. That's a time to have the TCAS or other traffic system on and working.
Under the changes in the AIM 2/9/12, was this:
http://www.faa.gov/air_traffic/publications/ATpubs/AIM/E%20of%20C%20Basic.html said:
c. 4-1-20. Transponder Operation
This change explains that transponders should be turned on prior to moving on the airport surface * as opposed to "as soon as possible".
so they went from asking to have it turned on prior to takeoff to having it on as soon as possible to having it on prior to movement on the surface. Sounds like they are reacting to complaints from planes with TCAS, but they still want it on prior to movement, regardless of whether the airport is towered or pilot controlled.
 
Yes Grant, but...

91.215 "trumps" the AIM, right?

(c) Transponder-on operation. While in the airspace as specified in paragraph (b) of this section or in all controlled airspace, each person operating an aircraft equipped with an operable ATC transponder maintained in accordance with §91.413 of this part shall operate the transponder, including Mode C equipment if installed, and shall reply on the appropriate code or as assigned by ATC.

The key word is "shall". There's no leeway given. And the airspace extends to the surface.

"Operating an aircraft" includes when it's not in motion, by FAA's rules.

The AIM tries to be saner, but the FAR is rigidly written. If they wanted to, they could have written it to say "see AIM".

What's even funnier is in section (d) instead of saying the FAA themselves could waive the requirement at any time for any reason, they painted themselves into a corner by stating only three specific circumstances where a controller may ask you to turn it off.

An ATIS announcement isn't in that list.

Very badly written.
 
And the airspace extends to the surface.

I beg to differ. Many other rules involving operating in airspace clearly do not apply to ground ops. Per your interpretation it would be a violation to taxi to the fuel pumps at an airport with Class E to the ground in IMC without an IFR clearance, or at any airport without an instrument rating and IR currency.
 
TAWS (and enhanced ground proximity warning) is supposed to be loud. Hitting the ground is much louder.

Disabling your traffic alert or response capabilities simply because your gear is down isn't a good idea. Your opportunities to trade paint increase exponentially as you approach the airport: coincidentaly this is also the time you'll be extending your gear. Almost every TCAS alert or resolution advisory that I've experienced has been near an airport. Not all, but most. That's a time to have the TCAS or other traffic system on and working.

I'm sorry, I'll just to disagree with you, and since it's my plane, I've made changes to those systems. TAWS and SKYWATCH were transmitting in all caps all the time. A simple warning in a reasonable tone was sufficient. The volume of these was such that I could not hear tower or ground when they went off. I've toned them down.

I linked SKYWATCH to the landing gear and am much happier with it. I was getting several warnings of traffic that was on the ground every time I landed at my home field. When I departed Friday, I got alerts as soon as I raised the gear on departure: it's highly distractive. Soon, one ignores it which isn't good. This is a very busy airport that is Class D under Class B. I was getting traffic alerts on every approach and they were all on the ground waiting to depart. I'd rather rely on tower, knowledge of the traffic and my runway scan.

With the volume tolerable now, it is better. My gear speed is 130 knots, I'm pretty close in when I lower the gear except in instrument conditions at the FAF. When this was most distractive was when I was coming in with low ceilings and getting multiple traffic alerts before going visual: very disruptive and I couldn't hear tower which isn't good.

Best,

Dave
 
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I beg to differ. Many other rules involving operating in airspace clearly do not apply to ground ops. Per your interpretation it would be a violation to taxi to the fuel pumps at an airport with Class E to the ground in IMC without an IFR clearance, or at any airport without an instrument rating and IR currency.

LOL... good point. Although if it's a controlled area of the ramp, you need a clearance anyway.

FAA is just awful at writing skills, is all. The technology regularly outpaces their ability to write clearly.

Just look at the mess of all the GPS approach types, which in ten years will simply be "follow the annunciations on the device we certified"... because the various approach types and all that silliness will just be a logic tree in the device by then.

Garmin got ahead of the tech on their latest transponders and made the (incorrect) assumption that the transponder should just shut itself off on the ground. Oops. Bummer.
 
In thinking about this thread it dawned on me that I have never gotten any traffic warnings on TCAS from airplanes on the ground, even at airports where having the transponder on while taxiing has been required for a long time. I assumed it was because of some programming logic, and it is. I found this.

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From page 28 in this document.
http://www.faa.gov/documentLibrary/media/Advisory_Circular/TCAS II V7.1 Intro booklet.pdf

I see that Dave is using something else called SKYWATCH. Probably some of these traffic systems which are not true TCAS don't have this kind of logic.

As far as the volume is concerned, I have not found that the volume of the TCAS or TAWS warnings are much different than the normal radio volume. If they are they probably need to be adjusted.
 
Sounds like a much better system (although mine might have worked that way). I had the old Bonser RADAR altimeter and we couldn't find a reasonable manner in which to get it fixed. A new installation would have been quite expensive, so, I'm flying without one---there, I said it. Now, I feel better (g). That may have been why I was getting all the distractive alerts, Best, Dave
 
Still getting some of the bugs out of this plane; always seems to take about a year after I purchase a bird to get it where I want it.

One of the biggest things I've had to filter through was deciding where to run the engines. Seems the POH settings are too cool and engines have had to go in for early TBO due to sulfidation issues. The local P&W gurus have told me the number one reason they rebuild engines is due to this.

So, in steps Tom Clements who wrote: The King Air Book. Tom explains in there that Beech derated the -21s so the C90 wouldn't compete with the E90 (g). Turns out they over rated the E90 -28 engines and folks running them at book were burning up turbine parts early. Tom points out how the C90-1 came out after Beech wasn't selling the E-90 and more and it had new power settings for the same -21 engine (which is what I have). Tom suggests running my engine at the same settings. I've done that and posted a panel pic to have folks send me messages telling me I'm running the engine too hot. So, I reevaluated. Tom has been wonderful in helping me and says the -21 will run just below redline all day because they were derated. He looked at my panel pic and said what I was doing was fine and should work out well.

So, after a lot of investigation and back and forth with some folks that disagreed, I've decided to follow Tom's advise and run the engines at the C90-1 power settings. Running them closer to red line should prevent sulfidation issues. I'm also checking with my mechanic and the local P&W guru who supervised my hot section.

I've also decided to get the TIT, Torque and one FF gauge recalibrated; although, Tom told me to check on other thing before adjusting the errant FF gauge to see if a shutoff occurs during start which would affect the gauge that is showing higher FF.

I'm also asking my folks to rerig my power levers. They are a bit uneven when I advance them and it's hard to bring up torque evenly. Beta is also off a bit and I'd like to get that corrected.

Best,

Dave
 
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