King Air C-90

Dave Siciliano said:
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.
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Very true. Although on the 310 I think it's going to take about 2-3 years, but that's because the work I have planned is more substantial. :)
 
It's been a long time since I've gone out to fly, just to go out and fly. Usually, I'm going to see family, doing practice approaches or using it for business. Today, I just flew down to Austin and back with friends to fly and we got lunch down there.
I'm still getting used to some things with just over 70 hours in the C90. I still love the way this thing launches off the runway on takeoff compared to the 58P. It holds a lot of fuel and one seldom needs a lot. I launched with less than half fuel today and two other pacs; climbed between 1,500 and 2,000 FPM. Departure steps me up much faster when they see I can climb at this rate at 140 to 150 IAS. I file higher on shorter trips because I can get up there so much more quickly. It's not just rate of climb, it's how departure and approach handle you. The plane is just so much quieter and vibration free. I hear the radios more clearly. With the glass in here, situation awareness is excellent. In bumpy conditions, it really handles better. I have to say, with the extra control and large rudder, it really makes me look like a pro when I land. I put it down in a 20 know direct cross wind last week. Right main touched a bit before the left, but smooth as could be. One almost has to quit flying the plane before they are fully on the ground to bump it in. Very nice handling.

Best,

Dave
 
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Glad to hear that you're having so much fun with the plane, Dave. No doubt, the King Air is popular for good reason!
 
Ted DuPuis said:
Glad to hear that you're having so much fun with the plane, Dave. No doubt, the King Air is popular for good reason!
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After reading his post, you'd almost think somebody had been telling him all that stuff for at least two years.;):D
 
That's the part about arbitrary red lines and percentages I don't like, I like solid numbers and red lines that indicate physical limitations.
 
I guess I just never noticed how many King Airs there are on frequency before since I wasn't listening for that call sign, but they seem to be everywhere!

Now that I'm more used to how the plane handles, climbs and descends, it's becoming a real pleasure to take trips. Austin slammed dunked me yesterday. I could see it coming. No problem with pulling the power back to get down. I do have to get approach flaps down to keep it from accelerating too quickly in the descent if that's of concern and have to bring the nose up a bit to get under 150 to bring the gear down. I was at 6,000 feet and had to get down to 2,000 pretty quickly to get on the ILS GS into Austin. If I couldn't have descended the way I did, I'm sure I would have been vectored all over.

Still love using beta to stop. I usually make the first turn off at Addison landing south after I touch down which makes it easy to taxi back to the FBO, that just wasn't doable in the 58P. Tower seems to love that I'm off very quickly after touchdown.

Best,

Dave
 
Henning said:
That's the part about arbitrary red lines and percentages I don't like, I like solid numbers and red lines that indicate physical limitations.
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Most red lines have a combination of technical reasons and arbitrary reasons. For example, the CHT limit on our piston engines are limits, but you can run your cylinders hotter and they won't fall off. If the limit was a true, hard limit, exceeding it would result in an instant failure. There's definitely a combination of needs of the equipment as well as needs of the installation.

Dave Siciliano said:
I guess I just never noticed how many King Airs there are on frequency before since I wasn't listening for that call sign, but they seem to be everywhere!

Now that I'm more used to how the plane handles, climbs and descends, it's becoming a real pleasure to take trips. Austin slammed dunked me yesterday. I could see it coming. No problem with pulling the power back to get down. I do have to get approach flaps down to keep it from accelerating too quickly in the descent if that's of concern and have to bring the nose up a bit to get under 150 to bring the gear down. I was at 6,000 feet and had to get down to 2,000 pretty quickly to get on the ILS GS into Austin. If I couldn't have descended the way I did, I'm sure I would have been vectored all over.

Still love using beta to stop. I usually make the first turn off at Addison landing south after I touch down which makes it easy to taxi back to the FBO, that just wasn't doable in the 58P. Tower seems to love that I'm off very quickly after touchdown.

Best,

Dave
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I have definitely noticed that turbine aircraft make ATC happier, especially when going into busy airspace. It seems to me the big reason is aircraft capability, especially with climbs and descents. Of course, then that gives you a higher bar to reach. I heard NY Approach complaining to a G-V the other day for not descending fast enough - he was doing 1,800 FPM.
 
Ted DuPuis said:
Most red lines have a combination of technical reasons and arbitrary reasons. For example, the CHT limit on our piston engines are limits, but you can run your cylinders hotter and they won't fall off. If the limit was a true, hard limit, exceeding it would result in an instant failure. There's definitely a combination of needs of the equipment as well as needs of the installation.



I have definitely noticed that turbine aircraft make ATC happier, especially when going into busy airspace. It seems to me the big reason is aircraft capability, especially with climbs and descents. Of course, then that gives you a higher bar to reach. I heard NY Approach complaining to a G-V the other day for not descending fast enough - he was doing 1,800 FPM.
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. Exactly, that's what I don't like, the melding of the two into a single datapoint especially when the logic behind it isn't thoroughly documented for situational analysis.
 
Henning said:
. Exactly, that's what I don't like, the melding of the two into a single datapoint especially when the logic behind it isn't thoroughly documented for situational analysis.
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Since we are dealing with something that is very dynamic and has millions of cycles in its life, setting a limit at the point of instant failure would be rather silly.

As a result, limits are imposed that do make sense for longevity. Basically "Go above this and you will have substantially lower life." The limits are not goals. Goals are then provided separately "Stay here and you will see a long and happy life." I'm not seeing the problem.
 
Of course, when any company markets a product, many folks have input. In some cases, the engineers prevail, in some marketing. Accounting may contribute. In the case of my plane with the -21 engines, a consideration was not competing with another product at the time: the E-90. Sulfidation issues didn't seem to be widely understood at the time. Who would have thought, running the engine a bit easier could shorten it's useful life to TBO?

We see it everywhere. In my part of the country, the geotech folks have had an exponential learning curve with soil expansion and contraction. Things are designed much differently now than just twenty years ago. More is understood. There are more materials and methods known to remediate. There are conflicting interests. How much of an expense should be passed along to a developer? What life cycle should be assumed when designing? Sometimes a proposed solution is still experimental and they true impact won't be known for years to come.

The KA is simply handled differently than the P Baron was by ATC/Approach. It's faster, climbs faster, can descend faster and the crew/pilot probably has more experience/training. It's not a beginner aircraft; is more expensive to maintain; and usually requires at least annual recurrent training. May have two person crews. Unbelievable how fast I can clear a runway after the mains touch. Put it in beta and it has a very short landing roll. The 58P just had brakes and one didn't want to use them a lot when going fast; so, usually they roll until they slow down; then, used brakes before turning. I can usually make the first turn off within about 1,000 feet of wheels touching and that's not maxing it out. Wheels touch, smoothly move props full forward; power levers smoothly back to beta and the plane just hunkers down and slows very quickly to 40 knots or so.

Best,

Dave
 
Ted DuPuis said:
Since we are dealing with something that is very dynamic and has millions of cycles in its life, setting a limit at the point of instant failure would be rather silly.

As a result, limits are imposed that do make sense for longevity. Basically "Go above this and you will have substantially lower life." The limits are not goals. Goals are then provided separately "Stay here and you will see a long and happy life." I'm not seeing the problem.
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I don't mind the limit being set so much as not having all the information as to the calculation. That's basically the issue that is being dealt with here. Without knowing all the factors of that calculation it's hard to determine where to run for best effect as situations and needs require for fine tuning. As was stated here, one of those redlines actually represents a marketing number so they could push the more expensive airplane. These are the things about aviation that really annoy me.
 
Ted DuPuis said:
I heard NY Approach complaining to a G-V the other day for not descending fast enough - he was doing 1,800 FPM.
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That isn't even a 3 degree rate of descent if they were doing 250 knots. Rule of thumb is groundspeed X 5 to get the rate of descent for 3 degrees.
 
Henning said:
I don't mind the limit being set so much as not having all the information as to the calculation. That's basically the issue that is being dealt with here. Without knowing all the factors of that calculation it's hard to determine where to run for best effect as situations and needs require for fine tuning. As was stated here, one of those redlines actually represents a marketing number so they could push the more expensive airplane. These are the things about aviation that really annoy me.
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I agree with you in principle, but I don't think that will ever happen. There are too many people outside of engineering who get to influence the end numbers for that to happen.

Additionally, I notice that when the manufacturer does come out and make recommendations and explain why, the end users end up often complaining and saying "That's a load of crap" anyway if it's not what they want to hear.
 
Everskyward said:
That isn't even a 3 degree rate of descent if they were doing 250 knots. Rule of thumb is groundspeed X 5 to get the rate of descent for 3 degrees.
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Really appreciate your tips! I liked the one about the taxi light for the lineman and use it all the time. Makes me feel more professional (g).
Sorry I couldn't break free last time you were in.

Best,

Dave
 
Everskyward said:
That isn't even a 3 degree rate of descent if they were doing 250 knots. Rule of thumb is groundspeed X 5 to get the rate of descent for 3 degrees.
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Huh? 5 x 250 = 1250 and 1800>that. :wink2:
 
Ted DuPuis said:
I agree with you in principle, but I don't think that will ever happen. There are too many people outside of engineering who get to influence the end numbers for that to happen.

Additionally, I notice that when the manufacturer does come out and make recommendations and explain why, the end users end up often complaining and saying "That's a load of crap" anyway if it's not what they want to hear.
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Well, the load of crap part may or may not be true from an engineering standpoint. It's the old "Boy who cried wolf" story, you feed feed people crap all the time they expect everything you bring to the table to be crap.
 
Henning said:
Well, the load of crap part may or may not be true from an engineering standpoint. It's the old "Boy who cried wolf" story, you feed feed people crap all the time they expect everything you bring to the table to be crap.
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People want to hear what they want to hear. If they decide that something sounds like a good idea, they don't like hearing it's not. I've seen that much more. Then again, I don't feed people crap.
 
That isn't even a 3 degree rate of descent if they were doing 250 knots. Rule of thumb is groundspeed X 5 to get the rate of descent for 3 degrees
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The general rule of thumb in turbine equipment is a 3:1 descent, not a 3 degree descent. The three degree descent only comes into play on an approach, and only then if it's a three degree glidepath. Usually one plans on starting the descent three miles out for every thousand feet to lose, and maintaining roughly that profile unless ATC requires otherwise.

In the New York area, it's not uncommon to be asked to really hoof it down to a lower altitude. 2,500 fpm is a good minimum descent rate if one has much altitude to lose. I try to keep it lower once below 10,000, because there's a higher chance of encountering slower traffic, and of course, the density is greater. Where ever possible, unless ATC or a procedure crossing restriction dictates otherwise, I try to keep to the general 3:1 descent profile.

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.
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I used to be the Director of Maintenance for a King Air emergency aeromedical operation. Unless you're running No. 2 diesel in your airplane, sulfur isn't an issue, and running at reduced power won't hurt your engine. Temperature is the enemy in turbine engines; you'll see a substantially happier engine with far less potential for hot section problems over the years, by running reduced power. The need to try to fine tune the gauge indications to the gnats backside should be overcome and eliminated; reduced power is your friend.

Getting your gauges calibrated is a wise idea.
 
DouglasBader said:
In the New York area, it's not uncommon to be asked to really hoof it down to a lower altitude. 2,500 fpm is a good minimum descent rate if one has much altitude to lose. I try to keep it lower once below 10,000, because there's a higher chance of encountering slower traffic, and of course, the density is greater. Where ever possible, unless ATC or a procedure crossing restriction dictates otherwise, I try to keep to the general 3:1 descent profile.
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Even in piston aircraft they will try to give you unreasonable descent profiles in New York. I was once asked for 2,000 fpm or greater in the Aztec. I complied, but was tempted not to just because the controller was acting like a jerk to me and others.

When you have passengers it gets to be more annoying since you want them to have a comfortable flight. Doubly so when it's Part 135 and they truly do have the option to go with someone else.

The converse is that I don't want to operate a turbine going in and out of these same areas, because these areas also will make you sit around burning excess fuel for longer on your way out. Pistons are nicer because you won't have a fuel burn hit like you will with turbines.
 
I watch an independent P&W consultant perform borescope inspections of numerous KA PT6-A innards, and have spent a fair amount of time discussing the heat-damage vs. sulfidation-damage issues with the Dallas Airmotive hot-section shop at DAL. Their observations, reports and repairs disagree with your theory.
DouglasBader said:
I used to be the Director of Maintenance for a King Air emergency aeromedical operation. Unless you're running No. 2 diesel in your airplane, sulfur isn't an issue, and running at reduced power won't hurt your engine. Temperature is the enemy in turbine engines; you'll see a substantially happier engine with far less potential for hot section problems over the years, by running reduced power. The need to try to fine tune the gauge indications to the gnats backside should be overcome and eliminated; reduced power is your friend.

Getting your gauges calibrated is a wise idea.
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DouglasBader said:
I used to be the Director of Maintenance for a King Air emergency aeromedical operation. Unless you're running No. 2 diesel in your airplane, sulfur isn't an issue, and running at reduced power won't hurt your engine. Temperature is the enemy in turbine engines; you'll see a substantially happier engine with far less potential for hot section problems over the years, by running reduced power. The need to try to fine tune the gauge indications to the gnats backside should be overcome and eliminated; reduced power is your friend.
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Poor advice, and a lack of observation once again.

Being "Director of Maintenance" is an FAA title for records keeping. Clearly you didn't pay any attention to the overhaul shops. Reduced power has quite definitely been shown to the cause of increased sulfidation.
 
I watch an independent P&W consultant perform borescope inspections of numerous KA PT6-A innards, and have spent a fair amount of time discussing the heat-damage vs. sulfidation-damage issues with the Dallas Airmotive hot-section shop at DAL. Their observations, reports and repairs disagree with your theory.
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It's not a theory, actually. Turbine Operations, 101.

Reduced power prologs life, at it's applicable in the PT6A as much as any turbojet or turbofan.

My work on and operation of PT6A's has been restricted mostly to -28's, -41's, -42's, -45's, -65's, -66's, and -67's, so I certainly haven't operated or seen them all, but I can tell you that for those, and all the training I've had on them and all the work I've done on them, which does include splitting and borescoping, one isn't hurting the engine by operating with reduced power. One is helping. If your'e having sulfidation, you're doing something wrong, and that applies to the aircraft I've operated and worked on that have the propellers behind the engine, as well as in front.

Being "Director of Maintenance" is an FAA title for records keeping. Clearly you didn't pay any attention to the overhaul shops.
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Record keeping is certainly one such function, but I spent the majority of my time on the shop floor with a wrench in my hand. I ran the place.

I've been DoM twice; once for a turboprop operation running King Air's and once for a turbojet operation using Sabreliners. I've been an inspector in repair stations, a line mechanic, shop mechanic, and few other things along the way, and yes, I've torn down and built up most kinds of powerplants over the years, including a lot of PT6A's.

Reduced power isn't harmful to the engine.

Trying to run up against the temperature limits isn't a good idea. A temperature reduction, however, is.
 
Doug: you probably haven't read through this entire thread. Appreciate your imput. The power settings we are following come from two sources: Tom Clements who wrote the book: "The King Air Book". Tom was with Beachcraft for years, instructed in all their planes and has written the training manuals at least one Sim school relies upon. He points out the -21s were under rated and can run at red line all day without a problem. As a matter of fact, Beech changed the power setting for the -21 when the C90-1 came out. That's where I run mine. The -28 was over rated and needs to be run below redline. Point is, the factory didn't always set the red line at the most advantageous point for an engine. Owners and maintenance folks have to work to figure out where that is.

The local P&W gurus have clearly said they are rebuilding engines primarily because of sulfidation issues from engines not being run hot enough. I know several folks that have had engines redone because of this issue. In the case of the -21 (which is what I have) that may because factory POH power settings run the engines pretty cool. The later revised power settings run them pretty close to redline.

Best,

Dave
 
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I can vouch for how quickly Dave's bird can slow down and make that first turnoff at Addison (see video below)... He generously took me and four others to Stephenville for Hard Eight BBQ today. We departed from Addison with Dave, me, and Al on board, then flew over to Bourland, where we picked up three others. With six on board on a hot Texas summer day, the C90B showed her prowess... We were off the 4100' runway in less than 2000', and a climbing left turn had us easily climbing through 3500' over the 873' MSL airport after just 270° of turn... WOW.

Thanks, Dave, for sharing right seat time and an incredible day with very interesting people!


 

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I had a great time Troy. Thanks for joining us.
What's the You Tube link in your post?

Best,

Dave
 
I was in front of you guys in the piper sport coming into KSEP. Thanks for giving me some room to land in front of you.
Your plane is a beauty.

Bill D.
 
txnightster said:
I was in front of you guys in the piper sport coming into KSEP. Thanks for giving me some room to land in front of you.
Your plane is a beauty.

Bill D.
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Red and white plane ending in Papa Sierra? That's a pretty LSA. Dis you depart from Addison? We waved at some guys in a Piper Sport who taxi'd past on their way to 15 while we were preflighting at Million Air.
 
Bill: SEP was a popular destination yesterday! We thought we'd be ahead of the crowd and were for the most part, but you and two others were in the pattern as we approached. We did a left 360 just to give everyone a chance to get down before we entered the left downwind. Beautiful day to fly, wasn't it?
It's a bit of an issue with the KA, sometimes our over take speed is pretty high even when we're not in a hurry. So, we enjoyed the scenery a bit more before getting in the pattern.
Bit of a problem for us to taxi too. Everyone takes the end parking spots and we have to taxi between planes to get to one. Can be hard with out larger wing span without a ground guide.
Hope you had a great visit.

Dave
 
Yes, that was us leaving from Addison. The plane is a rental from US Sport. Nice little bird but a touch warm on those hot days. Our takeoff climb was pretty sluggish.

It was nice to see everyone being courteous at KSEP. Between your KA and the Citation we were hustling to get out of the way. It was all the excuse I needed for a no flaps landing :). I was a little surprised that Hard 8 wasn't too busy and it was nice not to stand in line for 20 minutes for food.

The parking at KSEP can get crowded but it is neat to see the variety of planes. There were two cubs on the line that I was particularly excited to see.

Bill D.
 
More on sulfidation. Someone was nice enough to send me this by an engineer with the MORE priogram. They have a real interest in maintaining longer engine life. According to him, operating the engine hotter will only change where sulfidation occurs on the turbine blades. Interesting. http://www.helimx.com/article/gas-turbine-engines-instructions-continued-airworthiness-why-0" target="_blank">http://www.helimx.com/article/gas-turbine-engines-instructions-continued-airworthiness-why-0 Best, Dave
 
Isn't it a more pleasant experience for all when everyone's nice (g). Funny how some folks are in such a hurry to get a $100 hamburger on what is supposed to be a fun trip. Of course, everyone in Dallas seems to be in a hurry all the time, even when purportedly relaxing! Dave
 
Interesting. I hadn't thought about increased pollution as a source of sulfidation, but maybe that explains why the problem has become more pronounced in our area.

Dave Siciliano said:
More on sulfidation. Someone was nice enough to send me this by an engineer with the MORE priogram. They have a real interest in maintaining longer engine life. According to him, operating the engine hotter will only change where sulfidation occurs on the turbine blades. Interesting. http://www.helimx.com/article/gas-turbine-engines-instructions-continued-airworthiness-why-0" target="_blank">http://www.helimx.com/article/gas-turbine-engines-instructions-continued-airworthiness-why-0 Best, Dave
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txnightster said:
Yes, that was us leaving from Addison. The plane is a rental from US Sport. Nice little bird but a touch warm on those hot days. Our takeoff climb was pretty sluggish.

It was nice to see everyone being courteous at KSEP. Between your KA and the Citation we were hustling to get out of the way. It was all the excuse I needed for a no flaps landing :). I was a little surprised that Hard 8 wasn't too busy and it was nice not to stand in line for 20 minutes for food.

The parking at KSEP can get crowded but it is neat to see the variety of planes. There were two cubs on the line that I was particularly excited to see.

Bill D.
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That's great! We stopped at 50F for about a half hour and still beat you to KSEP! Did you play for a while on the way?
 
Dave Siciliano said:
More on sulfidation. Someone was nice enough to send me this by an engineer with the MORE priogram. They have a real interest in maintaining longer engine life. According to him, operating the engine hotter will only change where sulfidation occurs on the turbine blades. Interesting. http://www.helimx.com/article/gas-turbine-engines-instructions-continued-airworthiness-why-0" target="_blank">http://www.helimx.com/article/gas-turbine-engines-instructions-continued-airworthiness-why-0 Best, Dave
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This article concurs (see page 2).

http://www.aviationpros.com/article/10378159/sulfidation-turbine-blade-corrosion
 
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