to FIKI or not

[aviatoreb]

Just now, Blue on Top said:

I'm an aerodynamicist.  I can eliminate drag in many areas ... to a point.  I'm waiting for a comment (or two) from @mike_elliott  

Oh yeah!

Do mine!

E

 

[Blue on Top]

51 minutes ago, exM20K said:

Probably a question better answered by Ovation pilots.  I don’t think there are many non FIKI acclaims.  Mike E can answer.  He has flown one or 2.

I'm 100% agreeing with your numbers, @exM20K, but if a non-FIKI airplane is, say, 5-6 knots slower than book.  The 10 AMU is now down to 4 or 5 AMU, and Mr. @mike_elliott is going to be laughing at me  ... harder than normally.  IOW, I'm trying to scope the program to see if it is worth the effort.

[carusoam]

Seeing if Scott is around... @KSMooniac 

Have to get all the sharpest knives in the drawer...

Next topic.... World Peace achieved through Mooney aviation...   

Best regards,

-a-

[exM20K]

2 hours ago, Blue on Top said:

I'm 100% agreeing with your numbers, @exM20K, but if a non-FIKI airplane is, say, 5-6 knots slower than book.  The 10 AMU is now down to 4 or 5 AMU, and Mr. @mike_elliott is going to be laughing at me  ... harder than normally.  IOW, I'm trying to scope the program to see if it is worth the effort.

Maybe don't limit yourself.... maybe you can do better than factory/clean wing TN.  I'll ask the owner of a clean wing plane I know to do the same exercise I did, but really:  See what you can do to a TKS plane. 

I get it that the economics have to work, but if the cost to prove this out isn't extraordinary, I'm sure you could find someone to help finance the test.

 

Standing by,

-dan 

 

[FJC]

7 hours ago, GeeBee said:

Depends on the winds. IF you have to depart South, you have to usually do the "Golf Course Climb Out" where you shuttle climb over the golf course. I'll take a pretty significant tail wind to avoid that, but sometimes the numbers don't work. You basically have to land south, takeoff north. When landing south, pre plan the go around carefully. You should have several plans for go around at different points because at several points you have hills you cannot out climb in landing configuration or. accelerating there from. If it all goes to poop, go around straight ahead and climb over the golf course. If you decide to fly the IFR approach check your missed approach climb gradient.

KTRK IMHO is a little easier because you got 4 pretty good runways to choose from. It sits down in a bowl, but a big enough one that you can shuttle climb. The instrument approach into KTRK is a little wild because you have cumulus granite on both sides as you let down and the FAF on the RNAV 20 only has 1100 feet ground clearance due to a hill. Make sure you pay attention to cold weather altitude corrections as required as well as circling limitations. 

If you have not been up there you might want to engage an instructor for a "High Altitude Checkout".  I think Don Kaye lives near you. Might give him a call.

Yeah...Don is going to teach me how to get in/out of S. Tahoe safely!

[FJC]

7 hours ago, GeeBee said:

Depends on the winds. IF you have to depart South, you have to usually do the "Golf Course Climb Out" where you shuttle climb over the golf course. I'll take a pretty significant tail wind to avoid that, but sometimes the numbers don't work. You basically have to land south, takeoff north. When landing south, pre plan the go around carefully. You should have several plans for go around at different points because at several points you have hills you cannot out climb in landing configuration or. accelerating there from. If it all goes to poop, go around straight ahead and climb over the golf course. If you decide to fly the IFR approach check your missed approach climb gradient.

KTRK IMHO is a little easier because you got 4 pretty good runways to choose from. It sits down in a bowl, but a big enough one that you can shuttle climb. The instrument approach into KTRK is a little wild because you have cumulus granite on both sides as you let down and the FAF on the RNAV 20 only has 1100 feet ground clearance due to a hill. Make sure you pay attention to cold weather altitude corrections as required as well as circling limitations. 

If you have not been up there you might want to engage an instructor for a "High Altitude Checkout".  I think Don Kaye lives near you. Might give him a call.

Yeah...Don is going to teach me how to get in/out of S. Tahoe safely!

[carusoam]

That’s such a good idea, I’d say thrice!

-a-

[Blue on Top]

9 minutes ago, exM20K said:

Maybe don't limit yourself.... maybe you can do better than factory/clean wing TN.  I'll ask the owner of a clean wing plane I know to do the same exercise I did, but really:  See what you can do to a TKS plane. 

I get it that the economics have to work, but if the cost to prove this out isn't extraordinary, I'm sure you could find someone to help finance the test.  -dan 

@exM20K  I love your attitude!  And, ironically, were it not for Covid (and my wife and I not going back to Illinois for Christmas), I would hop in my car and buy you lunch at Pilot Pete's!

Costs for the tests are mainly aircraft time ... and my time doing the modification.  It's moving up my priority list.

[Blue on Top]

Whoever posted the article about the TB20 TKS system, thank you!  It is also a scab on system (after the airplane is built and added later).  The airfoil on that airplane is not as critical as the Mooney but a lot of the issues are similar.  The Mooney was also the first GA airplane with TKS.

Just because an airplane is FIKI, does not mean that one can fly into any condition.  There are icing conditions that can overwhelm every system ... even hot leading edges.  Been there ... don't want to do it again.   FIKI used properly allows the airplane to get out of the situation. 

[mike_elliott]

10 hours ago, Blue on Top said:

I'm an aerodynamicist.  I can eliminate drag in many areas ... to a point.  I'm waiting for a comment (or two) from @mike_elliott  

Ron, my Mark I sphincter gauge has a couple of the non fiki planes for sure making book. N281TA an Ultra Acclaim, and N914BC an older ovation were fast examples. N311TN I am sure would also, but she was Captain Mikey's development plane. Typically, I dont run em up to FL25 for a speed check, and rarely get into the FL's at my age. Here is one of the Ultras 50 LOP at 10K

 

[mike_elliott]

6 hours ago, Blue on Top said:

The Mooney was also the first GA airplane with TKS.

Ron Dubin owns that one now. Full disclaimer, Ron owns 2 other Mooney's and is cofounder of the Mooney Summit.

[Blue on Top]

@mike_elliott   Do you know why Mooney never made a change to make the TKS conformal to the airfoil shape?

[exM20K]

5 hours ago, mike_elliott said:

Here is one of the Ultras 50 LOP at 10K

I think someone has the alt static open lol.

You sure that's LOP? book at 10,000 is 205

 

ROP: 

[aviatoreb]

5 hours ago, mike_elliott said:

Ron, my Mark I sphincter gauge has a couple of the non fiki planes for sure making book. N281TA an Ultra Acclaim, and N914BC an older ovation were fast examples. N311TN I am sure would also, but she was Captain Mikey's development plane. Typically, I dont run em up to FL25 for a speed check, and rarely get into the FL's at my age. Here is one of the Ultras 50 LOP at 10K

 

Dang that's fast.

[mike_elliott]

49 minutes ago, Blue on Top said:

@mike_elliott   Do you know why Mooney never made a change to make the TKS conformal to the airfoil shape?

Might have a lot to do with the FAA, but dont know for certain. Ping Kevin H, he might know. Bob K might also.

[mike_elliott]

43 minutes ago, exM20K said:

I think someone has the alt static open lol.

You sure that's LOP? book at 10,000 is 205

 

ROP: 

Yea, Dan, This is the fastest one I have flown for sure. SN 31-0001 was a distant 2nd. Yea, it really was LOP, had to pull it back to keep it in the yellow. I think the charts you show were developed  from the test flights of 31-0001

[exM20K]

2 hours ago, mike_elliott said:

Might have a lot to do with the FAA, but dont know for certain. Ping Kevin H, he might know. Bob K might also.

My guess is it's a materials issue. If you look at how Diamond did it in the DA42, non-fiki planes have a fake  TKS panel that is replaced with the real thing when that option is specified.  It's not obvious how one could do that with a metal-skinned wing.

-dan

[aviatoreb]

9 hours ago, mike_elliott said:

Yea, Dan, This is the fastest one I have flown for sure. SN 31-0001 was a distant 2nd. Yea, it really was LOP, had to pull it back to keep it in the yellow. I think the charts you show were developed  from the test flights of 31-0001

I am curious - you have flown quite a few of this same model airplane.  You say this one is the fastest.  So for sake of understanding variability - forgive me if you know my profession - what would you say is average?  What would you say is slowest - in these newish M20TN's?  Head to head with tks and without.

[Niko182]

What makes the newer ones faster if you dont mind me asking. Does the fact the cowl lines up with the spinner make a difference?

[carusoam]

If you look at the scabbed on TKS panels.. there is a different curvature to the leading edge... with end affects... in a sensitive area...

It would take some fancy sheet metal work to be able to have replaceable leading edges...

But, alloys, bending, and cutting techniques have come a long way over the years...

 

The cool thing is... the higher you fly, the less additional air resistance is encountered... while the turbo keeps supplying power...

PP thoughts only...

Best regards,

-a-

[mike_elliott]

10 hours ago, aviatoreb said:

I am curious - you have flown quite a few of this same model airplane.  You say this one is the fastest.  So for sake of understanding variability - forgive me if you know my profession - what would you say is average?  What would you say is slowest - in these newish M20TN's?  Head to head with tks and without.

Eric, I would be doing your profession a disservice with my MK I sphincter readings. Simply flying the various Ultras at the same settings 29/24 50 LOP at the same altitude shows about a 5-8 kt difference from the non fiki ones fastest to slowest, and an additional 5 kts for the FIKI.

10 hours ago, Niko182 said:

What makes the newer ones faster if you dont mind me asking. Does the fact the cowl lines up with the spinner make a difference?

Money, thats all I can think of

 

[aviatoreb]

22 minutes ago, mike_elliott said:

Eric, I would be doing your profession a disservice with my MK I sphincter readings. Simply flying the various Ultras at the same settings 29/24 50 LOP at the same altitude shows about a 5-8 kt difference from the non fiki ones fastest to slowest, and an additional 5 kts for the FIKI.

Money, thats all I can think of

 

Thanks - its all I was hoping for was your impression and that is very interesting.

Erik

[Igor_U]

23 hours ago, exM20K said:

My guess is it's a materials issue. If you look at how Diamond did it in the DA42, non-fiki planes have a fake  TKS panel that is replaced with the real thing when that option is specified.  It's not obvious how one could do that with a metal-skinned wing.

-dan

I wasn't aware of that but makes sense not to have two tools...

Basically, Mooney TKS install is and afterthought where STC panels are installed on the existing Leading edge skin. Diamond and Cirrus have composite wing with LE recessed for the TKS panel so the surface can be smooth.

It is possible to design metallic LE to have flush surface and Hawker Jet did it years ago, but it is more complex and costly. See the attached picture. On my job I did some trade studies for a FTB we work on (very large experimental) but luckily, it wasn't required.

 

 

[Blue on Top]

4 hours ago, Igor_U said:

I wasn't aware of that but makes sense not to have two tools...

Basically, Mooney TKS install is and afterthought where STC panels are installed on the existing Leading edge skin. Diamond and Cirrus have composite wing with LE recessed for the TKS panel so the surface can be smooth.

It is possible to design metallic LE to have flush surface and Hawker Jet did it years ago, but it is more complex and costly. See the attached picture. On my job I did some trade studies for a FTB we work on (very large experimental) but luckily, it wasn't required.

 

 

These look like all the other ones that I have worked with at Cessna, Beech, Honda, etc.  I think that the main reason (as has been mentioned above) is that it was accomplished after the original wing was designed, and making changes is very, very expensive ... especially when the quantities are so low.