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Twin Performance Question

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Twin Performance Question

Postby 17031 » Mon Dec 21, 2015 3:24 pm

I'm considering trading my 260B for a turbo twin. I need the deice capability and I could use the added altitude the turbos provide. The performance specs I could find on the internet shows a difference between the model B's and C's. The B's show a cruise of 194kts and the C's a 209kts. Why the difference? Is it actual?
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Re: Twin Performance Question

Postby Kristin Winter » Mon Dec 21, 2015 7:16 pm

Not actual. I think Piper just changed the power setting charts. If anything, the B model may be a touch faster than the C model.

 

Have you found a deiced Twin? Those are rare.

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Re: Twin Performance Question

Postby N3322G » Tue Dec 22, 2015 2:00 pm

Ditto Kristin's response.

 

Biggest single difference between B and C models is a thicker stabilator on the C. After that, so many changes over the years of existence have blurred differences when they came out of the factory ie my 39 sn 10 now has the alt inop lights previously only put on sn 142 and up. Tiny example but indicative of the wide feature variation you will find now.

Be sure to get an experienced Comanche pre-buy and then learn to fly and maintain correctly. See Tech Tab stuff and CFF Tab

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Re: Twin Performance Question

Postby Charles Schefer » Tue Dec 22, 2015 9:59 pm

Keep in mind that turbos will add maintenance expense. You will get some added performance but I've been told by others on this forum that due to engine cooling drag, the turbo models are slower below about 8-9K MSL vs the normally aspirated but faster above. I think the total speed advantage high up may be 10-15 knots or so... I don't have the data to say. But for that little extra speed - you only get it higher up (slower down low) and at added fuel and maint cost. I looked for normally aspirated because I didn't feel the turbos were worth it. Also I've flown my non-turbo PA30 at 11-12K and it performs very well. Zach Grant says the non turbos are even very good at 14K so unless you want to fly high all the time I'd suggest looking normally aspirated. Just my 2-cents.

 

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Re: Twin Performance Question

Postby 17031 » Wed Dec 23, 2015 4:31 pm

Thanks all. The primary reason for the wanting the turbos is for altitude. To reliably get above weather I believe I'll need to get up to 22k or higher. More critical though is the de-icing equipment. There are two weather conditions I stay clear of, thunder storms and icing. I don't take chances with either but I can take the long route around thunder storms. Icing is a different matter. When there is an airmet for icing anywhere on my route I don't fly, period. I occasionally see twins with deicing equipment on the market and if I can find the right one and get it I would get the necessary training and hopefully be good to go. That's my thought process anyway. I am VERY happy with my 260B and having just put in a new 3-blade prop and rebuilt engine, I really would prefer to keep it.
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Re: Twin Performance Question

Postby JIMICS2452 » Thu Dec 24, 2015 1:25 pm

Where are you located? The local flying weather can have a big impact on the aircraft needed to dispatch in certain times of the year. If ice is often a big problem big problem in your area and you want to be able to go regularly you need at least a turbo Aztec with all the anti=ice equipment.
Last edited by JIMICS2452 on Thu Dec 24, 2015 6:48 pm, edited 1 time in total.
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Re: Twin Performance Question

Postby 17031 » Thu Dec 24, 2015 3:47 pm

Good question Jim. I live in central California, i.e. the central valley. We get most of our moisture for the year in the winter when temperatures can range between 35-60F. At altitude this creates ideal conditions for ice formation. You can check it out yourself by looking at the airmet maps on the AOPA or Aviation Weather Center web sites. In California we get this low lying cloud formation, more like a fog that sits a few hundred feet above the ground. The ceilings are usually only 2000-3000 feet, but you never know for sure and it can get much higher. Coming down through this isn't so bad because I know the ceilings and can see the tops. Last night coming back from LA was a good example. ATC brought me down smack in the middle of hard IFR conditions and as ice began forming I requested a lower altitude and got out of it right away. No problem. Taking off is another matter since I usually don't know the tops. Any ice that does form tends to be very light and if I could get very reliable information on the tops I could make better decisions, i.e. if I knew with certainty the tops were only 2,000 feet for example and only clouds with no precipitation, I know I would have no trouble and could fly with confidence. When it comes to flying maybe I'm too conservative, so under the current circumstances, I drive. (Spending 6 hours, or more, in California traffic for a 3 hour task is no fun.)
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Re: Twin Performance Question

Postby Kristin Winter » Thu Dec 24, 2015 6:16 pm

Ahhh! A fellow Californian.

 

Your need of some level of icing protection depends a little bit on where you want to go with the plane. If you have a need to cross the Sierras reliably during the winter, then I will second Jim's suggestion. A turbo Aztec is the most capable light twin when it comes to handling ice.

If you missions lie more in trips to SoCal or over to the coast, then a deiced Twinkie will work just fine. The important difference is that the freezing level is rarely so low that you can't shed the ice before landing. The turbo provides some additional capability, but comes with higher maintenance expenses.

BTW, I have a deiced Twinkie. If you want to see the system some time, I am up in Petaluma.

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Re: Twin Performance Question

Postby 17031 » Fri Dec 25, 2015 2:11 am

Why would a turbo Aztec be any better than a turbo twinkie?
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Re: Twin Performance Question

Postby Kristin Winter » Fri Dec 25, 2015 7:53 am

The factory turbo system is more robust and more user friendly as it is on all the time. The Aztec has a Cub wing which means it is very high lift and will stay in the air even badly contaminated with ice. It has hot props while the best you can get on a Twin C is alky props.
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Re: Twin Performance Question

Postby JIMICS2452 » Fri Dec 25, 2015 2:25 pm

And an Aztec has another 180 HP to help keep you aloft while you get out of the ice, especially on climb-out. I lived in Vancouver, WA when I bought my Aztec. I needed to cross the Cascade and Rocky mountains on a regular basis, even in the winter. I wanted a Twin Comanche, but after really looking at my requirements a turbo Aztec made more sense. I spent a lot of time sucking oxygen between 15K and 17K cruising above icing conditions.

 

The biggest downside is the increased fuel burn - 26-28 gph on average from take off to landing, 24-26 gph at cruise.

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Re: Twin Performance Question

Postby N8632Y » Sat Feb 20, 2016 11:24 pm

Tim,
Sorry if i'm a couple of months late to this conversation. You mentioned your concern and that prior to take off you don't the tops.

 

"Taking off is another matter since I usually don't know the tops. Any ice that does form tends to be very light and if I could get very reliable information on the tops I could make better decisions, i.e. if I knew with certainty the tops were only 2,000 feet for example and only clouds with no precipitation, I know I would have no trouble and could fly with confidence."

There's many products out there to help determine tops before you go, at any point in time along your route, of course nothing is a guarantee on any flight.
I usually reference area forecasts, airmets (Z), infrared pics and normal nexrad and radar. Dont' forget pireps, get and give. I like skew-T charts too, and even winds aloft and temps. I use a few sites but aviationweather.gov is pretty good, and has a good ice forecast page(s). I'm sure many here have their ways of determining tops.

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Re: Twin Performance Question

Postby Charles Schefer » Sun Feb 21, 2016 12:39 am

Regarding icing - the NOAA ADDS Weather on-line has a predictive icing page that provides a 6+ hour forecast on icing levels and probability at various altitudes. It only looks 6-12 hours ahead but I've found it quite good. Also keep in mind that the deicing or anti-icing options offered on PA-30s (quite rare as Kristin indicated in an earlier post) are not Certificated for Flight Into Known Icing (FIKI). If there is icing forecast having the boots does not make it legal to launch. Nevertheless it's a great help get out of trouble tool to have if you can find one.

 

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Re: Twin Performance Question

Postby Kristin Winter » Sun Feb 21, 2016 5:11 am

Charles,

 

Are you saying it is not legal to launch a Comanche into known icing conditions? If so, I am curious about where you find that in the regulations.

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Re: Twin Performance Question

Postby Charles Schefer » Sun Feb 21, 2016 4:13 pm

Deicing is separated into FIKI and non-FIKI systems. For instance our 2006 Cirrus has a TKS "weeping wing" system but it is not certificated for FIKI. It has to do with the level of testing the manufacturer goes thru. In circa 2009 Cirrus installed a better system and went thru FIKI certification with the FAA. The newest Cirrus is FIKI but only if there is above a certain volume of TKS fluid aboard.

 

Richard Collins wrote a good piece regarding the FIKI certification of his P210 - Link Here: http://www.flyingmag.com/safety/weather/madness-icing . Some FIKI aircraft - including a C340A I fly recently received a letter from the FAA taking away the FIKI status.

I am quite certain that my understanding of FIKI vs non-FIKI certification standards is correct as I've dealt with the FAA on it quite a bit on the Part 135 charter side. That said, it is only my belief or understanding that the Wiggins de-icing system that was optional on the PA-30 was not FIKI certified. I read somewhere that it was not FIKI. Correct me if I am wrong but the air used to inflate the boots came from a refillable tank in the tail section and not the outflow side of a vaccuum pump or similar. I'd have a hard time believing the FAA would FIKI certify something like that but maybe I am wrong.

I'll try to pull the regulatory references for you on FIKI vs non-FIKI. As far as the PA-30 non-FIKI status goes - I feel confident in my statement but I can't say I am 100% on that.

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Re: Twin Performance Question

Postby Charles Schefer » Sun Feb 21, 2016 5:22 pm

I am not intending to hijack this thread but I recall the original post did involve icing...

Thanks Kristin I've learned some things...

I just did some more research on this after reading Kristin's reply and it seems that while the 135 regs that I am used to are pretty clear on the issue it's a bit more murky under Part 91. We could have a separate discussion on what is "safe" or "smart" but here I am looking specifically at what is "legal".

In doing some quick research I came across the following interesting reads. I won't regurgitate all the articles say but they are worth a read. I'll give a few highlights below...

https://www.faasafety.gov/gslac/ALC/cou ... eview=true
http://www.aerolegalservices.com/Articl ... 2-25.shtml
http://www.aopa.org/News-and-Video/All- ... definition

As I surmised earlier the FIKI / non-FIKI classification of icing systems really comes down to the certification process (and standards/regs) the manufacturer when thru (or not) during certification of the aircraft with that system.

Part 91 it's murky. There is no specific icing reference in Part 91 other than 91.527 which does not apply to our smaller aircraft. AIM 7-1-22 does discuss "known icing".

91.9(a) states that a pilot must comply with the operating limitations of the aircraft per the manufacturer (Section 2 of the AFM/POH - Limitations).

- In the case of my Cirrus aircraft the limitations section does in fact state "Flight Into Known Icing Prohibited". Newer Cirrus with the FIKI certified system do not have this limitation.

- The original AFM (circa 1968) for my PA-30 has no such limitation I can find in the Limitations Section.

- The ICS (Killough) AFM for the PA-30 states on Page 2-5 "Flight into known icing conditions is prohibited unless the following equipment is installed and working in accordance with applicable Piper drawings and FAA regulations..." It then goes on to list the STC equipment for what I assume is the Wiggins system.

More on the Limitations Section the above at the end of this post...

91.13(a) prohibits careless or reckless operation. Whether intentionally launching into FIKI conditions in a non-FIKI aircraft is considered "careless or reckless" is subject to interpretation.

FAR 91.103 specifies that "each pilot in command shall, before beginning a night become familiar with all available information concerning that flight: including weather reports and forecasts for flights under IFR or not in the vicinity of the airport."

It seems there is legal case history to show that the FAA and NTSB have used the regs above in certification action against pilots (Part 91) when icing was a causal factor in an incident or accident. That said it's clearly open for debate and interpretation. One of the legal references above concludes:

"At the end of the day, this Legal Interpretation does not give pilots a "bright-line" test to use in answering the "known icing conditions" question. However, it makes clear that pilots will still need to evaluate all available information both before and during a flight in order to make a reasonable determination as to whether "known icing conditions" are present along the proposed route of flight. Pilots will also need to be able to prove that they performed this evaluation if they find themselves defending against an alleged violation arising from an icing situation."

Going back to 91.9(a) and the AFM Limitations section. From a purely legal standpoint (irrespective of what is smart) I suppose if you want to launch a Wiggins equipped PA-30 into known icing it is not illegal based on the statement in the ICS AFM/POH on page 2-5. However if you have a non-Wiggins equipped PA-30/39 (or PA-24) as most of us do, AND you are using the ICS AFM - then yes it is illegal to launch based on the limitation on Page 2-5 and FAR 91.9(a). I suppose you could get around the limitation by reverting back to the original Piper AFM/POH from the 1950s-1960s which appears to remain silent on the issue.

This is my read....

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Re: Twin Performance Question

Postby Kristin Winter » Sun Feb 21, 2016 6:56 pm

Charles,

That is basically my understanding as well. There is a lot of confusion about this in the general population of GA pilots. There is no prohibition about launching your non-deiced Comanche, or any other CAR 3 certified aircraft into icing conditions, known or otherwise. "Known Icing" is purely a certification. You are correct that if you load up with ice and crash, you are likely to run into an enforcement action based on 91.13, but in absence of crashing, the FAA would have a very hard case to make.

It is helpful to consider that there are two bases for the certification of deicing/anti-icing equipment on aircraft. Prior to a revision to Part 23 in the 70's, or there abouts, all the manufacturer had to do to put icing equipment on the plane was to show that it wouldn't harm the flight characteristics. This can be thought of as "no harm" systems. They did not have to show that they worked to actually protect against icing. At a certain point, the manufacturers had to show that the systems would actually allow the airplane to fly safely in certain icing conditions. This new section was titled "Flight into Known Icing Conditions" i.e. FIKI. With aircraft certified after FIKI came into effect, either had the equipment which had been proved, or they got the limitation in the AFM. It is indeed illegal to fly most Part 23 certified aircraft into known icing conditions when the prohibition is in the AFM.

One of the things that confuse folks, and confused me until the FAA forced me to do the research when an ASI went off the deep end and tried to ground our fleet Aztec, is the aircraft that have the deicing equipment but are CAR 3 aircraft. Our 1974 Aztec's AFM did not state a limitation, rather it said that the aircraft could handle light to moderate icing conditions if the following equipment was installed, and then it listed the entire deice package. The ASI said I couldn't operate that aircraft 135 unless it was FIKI approved. He was wrong as AC 135-9 pointed out and I even confirmed it with top FAA folks in Washington. The 135 regs at that time, which may have changed, only state that you have to have deicing equipment covering each wing, tail, etc, but said nothing about FIKI certification. Our 1976 Navajos were also not FIKI, but the ASI didn't seem to know that as he didn't raise that issue. However, both carry ice better than some FIKI certified aircraft, so it would be hard to argue careless or reckless with these aircraft.

So yes, you can fly your 180 Comanche into known ice. I have put ice on most all light aircraft I have flown, as that is sort of what happens when you fly up north. Mostly it has never been more than a trace on the leading edge, but I knew that I was going to get the ice when descending through that 1000 foot layer while being vectored for the approach. It is a fact of life half of the year up north. I think that is one reason that the FAA has not promulgated a Part 91 ban on flight into known icing conditions until so certified as it could shut down most GA in the U.S. for half the year.

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Re: Twin Performance Question

Postby Charles Schefer » Mon Feb 22, 2016 2:03 am

Thanks Kristin, I learned something looking into this. My frame of reference was a newer certified aircraft (Cirrus) with a non-FIKI TKS system and the prohibition in the Limitations section so it seemed pretty clear to me in that regard. I think that with newer aircraft it is more clear as you highlight. Until this thread it never dawned on me that due to the absence of the limitation in older AFMs for older aircraft it is therefore legal (or not "illegal").

For the reasons stated in my earlier post I'd still say there is room to argue either way in the gray areas and you can be the FAA would leverage that gray area to support their argument in an enforcement action.

I think it's also clearly true that any PA-30 / 39 / 24 using the newer ICS AFM does have the limitation in the AFM unless the aircraft has the Wiggins system (I am assuming the PA-24 AFM is similar to the PA-30 AFM I have). Therefore due to FAR 91.9(a) and the limitation on page 2-5 of the ICS AFM - that does make it illegal. If you want to launch into known ice in your Comanche you have ditch the ICS AFM and claim the original AFM as your aircraft's "current" flight manual.

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Re: Twin Performance Question

Postby Charles Schefer » Mon Feb 22, 2016 2:06 am

 
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Re: Twin Performance Question

Postby GMTW » Mon Feb 22, 2016 2:59 am

Wiggins had more than one boot system, one is activated by a nitrogen bootle in the luggage compartment and one that came out in the late 60's that is pump activated. The POH says that "flight into known icing not approved unless equipped with two wiggins stc's which are the pump boots and the alcohol props and the hot plate installed iaw the piper drawing."
I have a pa39 that is equipped this way so if I'm challenged I'll argue. That being said I continue to avoid ice like the plague but have been thankful to have the equipment. The system seems to boot ice well.

I also have turbo's on the aircraft and like them. I fly where mea's are as high as 16000 ft and the turbos make the aircraft. It's true the aircraft is a little slower below 8000 ft but above that it comes alive.

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Re: Twin Performance Question

Postby Kristin Winter » Mon Feb 22, 2016 3:16 am

Charles,

I agree that most folks that are using the Killough manual as the AFM have a limitation. However, I bet that 99%+ of those using the manual, have never made it official with a 337 or even a logbook entry. Since the Killough manual is approved, it would seem that it need be officially adopted through some paperwork. My gut feeling is that it is a major alteration so needs a 337. Of course, most who are using the Killough manual probably don't have the original Piper mimeographed sheets which constitute the AFM, so defending a 91.9 bust by saying that the Killough manual is not the AFM would leave most open to an enforcement action for not having an AFM with the limitations. I keep the Killough manual in my plane, but it has market as for information only and not the AFM.

Interestingly, Supplement #1 to Piper report 1515 which is what applies to my C model Twinkie addresses the issue by stating: "The following items of equipment must be installed and operable to effectively cope with normally encountered icing conditions:" It then goes on to list the Wiggins equipment. Needless to say, this is informational and not regulatory.

I believe that starting around 1976, the FAA has been coercing the manufacturers to add a limitation to the AFM, even ones that were certified under CAR 3. The Aztec AFM was changed to require its deicing package -- non-FIKI though it is -- to fly into icing conditions. Though it is in the limitations section, the wording is rather ambiguous so I could likely mount a decent defense to an enforcement action based on 91.9. Killough came right out and said it was prohibited and the FAA bought off on it as an STC, so I do think that if you are using that for an AFM you are stuck. I would recommend that everyone with a Comanche make sure that they have the original as they official AFM and just use Killough for planning purposes.

A Cirrus without TKS is very scary in the ice. I would even take an equipped, non-FIKI Aztec over a FIKI Cirrus. Without the TKS, the Cirrus apparently has little intrinsic ability to handle ice. Even without deicing equipment, I think it would take a lot of ice to bring down an Aztec.

Last edited by Kristin Winter on Mon Feb 22, 2016 3:39 am, edited 1 time in total.
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Re: Twin Performance Question

Postby Kristin Winter » Mon Feb 22, 2016 3:25 am

 
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Re: Twin Performance Question

Postby GMTW » Mon Feb 22, 2016 3:58 am

Kristin;

I'm quoting kellog but i think the piper is similar; I'll go back to the airport tomorrow and check. I had piper send me a copy of the original so I had a starting point.

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Re: Twin Performance Question

Postby Kristin Winter » Mon Feb 22, 2016 4:02 am

Did you get the original for your airplane or a generic copy? What did they charge you for that?
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Re: Twin Performance Question

Postby Charles Schefer » Mon Feb 22, 2016 4:18 am

Kristin, you are right about the Cirrus wing. Fantastic wing but very high loading of 25lbs / sq-ft. I imagine the Hershey-bar Az-truck wing would be more forgiving of ice. However the FIKI cert SR-22 model is very capable in ice and it has an advantage in run back icing. I've flown one thru moderate-heavy icing conditions and the TKS kept the whole airframe clean. That said it wasn't a by choice encounter. I believe ALL aircraft especially light aircraft should aggressively avoid icing. The thing I don't like about TKS (other than the mess it leaves dripping on the hangar floor for days) is that you can run out!

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Re: Twin Performance Question

Postby Kristin Winter » Mon Feb 22, 2016 5:24 am

I always considered the deicing equipment as just incrementally better than none at all. My strategy for a flight was the crucial element, deiced or non-deiced. Deiced just gives me a little bit longer to be in it so I can climb or descend through a bit thicker, nastier layer than I might otherwise. I have put ice on an airplane hundreds of times, but never gotten to where the aircraft was thinking about not flying any more or requiring me to sacrifice altitude to maintain speed.

I have always thought the FAA went about icing all back asswards. Since there is no such thing as a light airplane, or maybe any airplane, that is impervious to ice, regardless of how it is equipped, it seems to me that we need "known icing" pilots. Training would save more lives. Instead, all you get from the FAA is "don't fly in it". They don't tell you what kind of ice to worry most about. How to have a strategy or how to figure your escape routes.

I will give you the point about run back ice, but all it will likely take is an altitude change to get the ice to do something other than start to build a ridge behind the boots. Again, this is something that ought to be taught. There is a world of difference between half an inch of rime on the leading edge and ice building a spoiler on top of the wing.

Running out of fluid would be ugly in a Cirrus. I wonder if the parachute is FIKI certified.

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Re: Twin Performance Question

Postby N8632Y » Mon Feb 22, 2016 12:19 pm

Training for "Ice" a great idea, and maybe an endorsement like high altitude, just another atmospheric phenom....
My old buddy fly in Alaska for 25 yrs, never with de ice equip, mostly Aztecs.
He said they were great, he would talk of cycling the prop, or quick pitch changes to bust off ice. He once had his gear iced and stuck up. Told the tower he was gone out over bay for awhile till the warmer air melted the iced up gear. Yes, it's the pilot that makes or breaks the plane, not vice versa.

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Re: Twin Performance Question

Postby Charles Schefer » Mon Feb 22, 2016 1:54 pm

100% agree on the training point.
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Re: Twin Performance Question

Postby Charles Schefer » Mon Feb 22, 2016 2:37 pm

One other comment for discussion that just occurred to me regarding which AFM is used as the official AFM (and I realize this is starting to stray from the original purpose of the thread)... I have been told that if you have a newer airspeed indicator in knots instead of mph that you must also have an AFM in knots. Assuming that is correct (I have not throughly researched it) then if you have... say an Aspen PFD displaying knots then you need the newer ICS AFM as your official AFM with knots for various reference speeds in the book.

Thoughts?

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Re: Twin Performance Question

Postby Kristin Winter » Mon Feb 22, 2016 8:21 pm

 
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Re: Twin Performance Question

Postby Charles Schefer » Mon Feb 22, 2016 10:15 pm

Kristin - all good points.

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Re: Twin Performance Question

Postby Charles Schefer » Tue Mar 01, 2016 5:54 pm

I finally got a chance to talk with my PMI at the Washington (DC) FSDO yesterday. I laid out the issue and he said no 337 and no logbook entry required to use the ICS AFM. He asked "is it an FAA Approved Flight Manual" and I said "yes it says so on the cover". He then asked in turn: "so why would you need any other FAA approval if it's already approved?". He said just stick it in and use it. He said if you feel more comfortable keep both the ICS and the original aboard but he said no 337 nor a log entry is required.

So playing Devil's advocate I asked "ok well if I buy an STC product that is also FAA Approved - I still have to file a 337 for the already approved change and do a log entry..." He said yes - that's because it's an alteration to the aircraft that affects performance and it's altering the approved baseline manual (i.e. with a new supplement). He said simply switching to a different fully approved manual does not require any additional approval.

So there you have it... you can agree or disagree but that is the Washington FSDO's position.

- Charles

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Re: Twin Performance Question

Postby Timothy Poole » Tue Mar 01, 2016 6:09 pm

 
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Re: Twin Performance Question

Postby Kristin Winter » Tue Mar 01, 2016 8:28 pm

I have sent it to my FSDO and we will see what they make of it. Based on the response you got, I am not entirely certain that they understood the question. I wouldn't say that a new AFM with different limitations does not affect performance.
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Re: Twin Performance Question

Postby Charles Schefer » Wed Mar 02, 2016 3:16 pm

Tim - You called it :) but who else could it be when it comes to maintenance at our local FSDO? :) I've actually found him to be quite a stickler for detail over the years.

Kristin - I don't disagree with you, I'm just sharing one inspector's response. I think he understood the issue just fine, we had a detailed discussion and he is a detail guy. I'm curious as to what your FSDO says. In my experience I've found different FSDOs will sometimes give different responses to the same question. In fact often two inspectors from the same FSDO won't agree. Such is the "clear cut" realm we live in :).

As an attorney I'm sure you'd agree that the Judicial branch of government exists to interpret the law. The law (including FAA regs) is not always clear-cut. So there is often room to debate and interpret.

- Charles

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Re: Twin Performance Question

Postby Kristin Winter » Wed Mar 02, 2016 9:32 pm

FAA regs are anything but clear cut, and even the FAA recognizes that it has a problem with varying interpretations among the different offices.

I will let you know when I hear back from my FSDO. I emailed it to them as I was not about to drive down to Oakland to knock on the door. Depending on what I hear, I may run this up the flag pole to FAA legal in DC. As an IA, I rather need to know if there is paperwork that needs to be done to count the Killough manual as the official AFM.

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Re: Twin Performance Question

Postby Charles Schefer » Wed Mar 02, 2016 9:48 pm

Makes sense Kristin. I'm interested to learn what you hear back...

- Charles

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Re: Twin Performance Question

Postby Charles Schefer » Mon Mar 07, 2016 2:24 pm

On the related subject of certification standards for FIKI it looks like ATSM is publishing new standards where it will no longer be a "one size fits all approach". Sounds like a good thing...

http://www.avweb.com/avwebflash/news/AS ... 797-1.html

- Charles

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