The need for speed

[PJClark]

Flew a couple of quick hops to visit our daughter yesterday so we stayed low.  I don't keep track except by "feel" but 180 KTAS at 6500 MSL feels about 5 knots faster than normal.  Must be a sweet spot in some complex temperature/pressure/humidity curve.

Whatever it is it makes me smile. 65%, 30", 2250 rpm, 18.5 gph, 1550 TIT.

Genuinely curious: anyone know if an Ovation or Acclaim will do this on 65% power at this low altitude?

[aviatoreb]

45 minutes ago, PJClark said:

Flew a couple of quick hops to visit our daughter yesterday so we stayed low.  I don't keep track except by "feel" but 180 KTAS at 6500 MSL feels about 5 knots faster than normal.  Must be a sweet spot in some complex temperature/pressure/humidity curve.

Whatever it is it makes me smile. 65%, 30", 2250 rpm, 18.5 gph, 1550 TIT.

Genuinely curious: anyone know if an Ovation or Acclaim will do this on 65% power at this low altitude?

Does your screen show OAT?  What was the OAT?

I think your rocket is ~5 knots faster than mine at that altitude but I have always blamed my tks for stealing about 5 knots.

[PJClark]

OAT along the bottom edge 40 F.

If TKS only costs you 5 knots probably good!

[Missile=Awesome]

What are winds doing?  I had 200knots at 5500 burning 12.5 23MP 25RPM yesterday in my Missile.

[aviatoreb]

56 minutes ago, PJClark said:

OAT along the bottom edge 40 F.

If TKS only costs you 5 knots probably good!

Sometimes I think it costs me 7 or 8 sometimes I think it is 5 - it is hard to tell for sure.  And it may depend on altitude.   But I call it 5.  My machine will do the same TAS at 6500 but it would take a higher setting so even more fuel.

[aviatoreb]

34 minutes ago, Missile=Awesome said:

What are winds doing?  I had 200knots at 5500 burning 12.5 23MP 25RPM yesterday in my Missile.

His panel says TAS is 180 and GS is also 180.

When bragging speed it is exciting to talk GS but not a great indicator of the airplane as much as it is the wind and the luck of the direction of travel.  A balloon will do 200GS with "enough wind".  My top ground speed I have seen is 327GS.  

I know though that at 6500 a missile is much more efficient and likely faster than my rocket.  I have ridden in Seth's beautiful machine and I am very impressed.  The IO550 is fantastic.  

As far as I have seen watching people report their speeds across many threads over time here, the acclaim, ovation, and missile will easily do 180 at 6500 and on less fuel than a rocket which can also do 180 at 6500 but on lots more fuel.

[exM20K]

18.5 gph @ 8000 standard day, book says 201KTAS. Real world prolly 10 under that.

love that PFD display.  It’s so much better and brighter than the G1000 especially turn and slip indication. 
-Dan 

Edited November 29, 2020 by exM20K

[Davidv]

1 hour ago, aviatoreb said:

His panel says TAS is 180 and GS is also 180.

When bragging speed it is exciting to talk GS but not a great indicator of the airplane as much as it is the wind and the luck of the direction of travel.  A balloon will do 200GS with "enough wind".  My top ground speed I have seen is 327GS.  

I know though that at 6500 a missile is much more efficient and likely faster than my rocket.  I have ridden in Seth's beautiful machine and I am very impressed.  The IO550 is fantastic.  

As far as I have seen watching people report their speeds across many threads over time here, the acclaim, ovation, and missile will easily do 180 at 6500 and on less fuel than a rocket which can also do 180 at 6500 but on lots more fuel.

I'm not trying to knock other pilots but it's always surprising when people don't know their own TAS.  It's really the only measure of true performance. Before I had a fancy EFIS with a temperature gauge I would use my ASI to calculate TAS and sometimes pull out the e6b to verify.  It was mostly from the natural Mooney paranoia that your airplane is slower than everyone else who has the same model . 

[Guest]

Speaking of TAS, it’s mostly related to 100LL. If you want more of the first, you need more of the second.

Clarence

[carusoam]

Got to love the laminar flow wing..!!!

And when that doesn’t work...

Exchange the 100LL for Jet A... then find Tom’s panel pics...   

Does the Lancair 4P have a laminar flow wing as well?

As far as the O and 65%bhp goes...

One has to first decide what 100% is for an IO550...

310hp powered O3s have reported speeds of 190s in cruise... Flaming Dragon mode on!

Best regards,

-a-

[aviatoreb]

1 hour ago, M20Doc said:

Speaking of TAS, it’s mostly related to 100LL. If you want more of the first, you need more of the second.

Clarence

That's very fast.  Especially at that altitude.  Is that a typical cruise speed and cruise setting.  199...oh so close to 200.  Can't you saw off a step or something and make it an honest 200?

[Guest]

14 minutes ago, aviatoreb said:

That's very fast.  Especially at that altitude.  Is that a typical cruise speed and cruise setting.  199...oh so close to 200.  Can't you saw off a step or something and make it an honest 200?

When I first got it, I ran it a little harder than I do now.  An honest 190-195 up to 10000’ is typical on 18-20gph.  I don’t know how much more can be squeezed out of it, it’s old like the owner.

Clarence

 

[aviatoreb]

2 minutes ago, M20Doc said:

When I first got it, I ran it a little harder than I do now.  An honest 190-195 up to 10000’ is typical on 18-20gph.  I don’t know how much more can be squeezed out of it, it’s old like the owner.

Clarence

 

Seems like it’s still kicking.  Seems like you must still be kicking too!

how much fuel flow and percent power did that 199tas take?

[Seth]

On 11/29/2020 at 11:26 AM, aviatoreb said:

Sometimes I think it costs me 7 or 8 sometimes I think it is 5 - it is hard to tell for sure.  And it may depend on altitude.   But I call it 5.  My machine will do the same TAS at 6500 but it would take a higher setting so even more fuel.

Erik-

It should cost you less at altitude where the air is less dense, hence less drag. So you are correct that sometimes it costs you 5 and other times 7 or 8. And I know you know this, just reminding you!

-Seth

[aviatoreb]

49 minutes ago, Seth said:

Erik-

It should cost you less at altitude where the air is less dense, hence less drag. So you are correct that sometimes it costs you 5 and other times 7 or 8. And I know you know this, just reminding you!

-Seth

Exactly.

[PJClark]

On 11/29/2020 at 6:59 PM, M20Doc said:

Speaking of TAS, it’s mostly related to 100LL. If you want more of the first, you need more of the second.

Clarence

What is that? Acclaim?  Or not a Mooney? 184 indicated in level flight is incredible

[tmo]

I'd guess it's the fire-breathing IO-720 in the Comanche-400...

[Guest]

2 hours ago, PJClark said:

What is that? Acclaim?  Or not a Mooney? 184 indicated in level flight is incredible

We’re not supposed to mention other brands here on Mooneyspace, but it’s a Piper Comanche 400.  Pipers improved copy of a Mooney!

Clarence

[Guest]

On 11/29/2020 at 8:39 PM, aviatoreb said:

Seems like it’s still kicking.  Seems like you must still be kicking too!

how much fuel flow and percent power did that 199tas take?

75% power(300HP) and about 20 gph.

Clarence

[aviatoreb]

8 minutes ago, M20Doc said:

75% power(300HP) and about 20 gph.

Clarence

Wow now that’s efficiency.  My engine is at 98% to produce 300hp and I don’t know the fuel flow at that setting but I have 100% so 305hp flowing at 33gph.  So 20gph is tremendous.

[Guest]

5 minutes ago, aviatoreb said:

Wow now that’s efficiency.  My engine is at 98% to produce 300hp and I don’t know the fuel flow at that setting but I have 100% so 305hp flowing at 33gph.  So 20gph is tremendous.

Finally a convert!  Now just several thousand other Mooney owners to convince.

Clarence

[aviatoreb]

8 minutes ago, M20Doc said:

Finally a convert!  Now just several thousand other Mooney owners to convince.

Clarence

I’m not kidding I’m seriously impressed!  Another way to say it / my 75% is only 229hp and my book says 21gph.

ok this time I mean it !... when this pandemic thing passes and M. Trudeau let’s me cross the border again I want to finally come to try and sneak a ride with you in your fab machine.

E

[Guest]

14 minutes ago, aviatoreb said:

I’m not kidding I’m seriously impressed!  Another way to say it / my 75% is only 229hp and my book says 21gph.

ok this time I mean it !... when this pandemic thing passes and M. Trudeau let’s me cross the border again I want to finally come to try and sneak a ride with you in your fab machine.

E

I’m sure we can work that out when the world returns to some semblance of normal.

Clarence

[aviatoreb]

8 minutes ago, M20Doc said:

I’m sure we can work that out when the world returns to some semblance of normal.

Clarence

:-)

[PJClark]

Ah. I was pretty sure that was no kind of Mooney, or at best, an Acclaim at 100% power and headed for new cylinders!

That IS phenomenal. But what a demo of the power of parasite drag.  200 hp gets us 180 KTAS.  The next 100 hp gets us another measly 20 KTAS.  Those are 20 awesome, beautiful KTAS, but still,you gotta hate the physics!