Armed Polite Society
December 11, 2017, 09:16:10 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News:
 
   Home   Help Search Login Register  
Pages: [1] 2
  Print  
Author Topic: Bush Pilots / Carbon Cub / Power time limit? / Huh?  (Read 303 times)
230RN
friend
Senior Member
***
Posts: 9,781


I resent being prejudged as a racist.


« on: December 07, 2017, 01:50:23 AM »

I like watching videos of bush pilots doing their thing --landing on a single rock and taking off in 3 feet.  But then I came across a plane I had not heard of, the "Carbon Cub."  I figured it was a Piper Cub outfitted with carbon fiber members, etc, so I looked it up:

https://en.wikipedia.org/wiki/CubCrafters_CC11-160_Carbon_Cub_SS

Quote
Carbon Cub SS is an ASTM certified light-sport aircraft based on the Piper Cub. It is modernized, with light-weight carbon fiber components and a 180 hp engine.[2]

Yeah, OK, but then I read:

Quote
The Carbon Cub SS was originally named the "CubCrafters Super Sport Cub".  In order to maintain certification under American Light Sport Aircraft limitations the maximum takeoff power is limited to five minutes.

To this groundlubber, that bolded portion is meaningless.  

Does anyone have a "Maximum Takeoff Power for Dummies" explanation of why some kind of time limitation is involved?  What the heck are they talking about?

Terry

Logged

When Democrats use the techniques they learned from Goebbels - was that cultural appropriation?
(With apologies to fistful.)
"Jerry... just remember... it's not a lie... if you believe it." --George Costanza.
(With thanks to George Costanza.)
dogmush
friend
Senior Member
***
Posts: 5,969


« Reply #1 on: December 07, 2017, 02:44:28 AM »

The engine is capable of a power level that will damage it if sustained. Because the aircraft is designed for short, power intensive maneuvers, they let pilots rev it that hard, but state you have to throttle back before 5 min to avoid damage.

It's rated for 180hp, but you can only get that 1i0 for 5 min before you have to throttle back to some lesser output, in this case 80hp.
Logged
Firethorn
friend
Senior Member
***
Posts: 5,158


Where'd my explosive space modulator go?


« Reply #2 on: December 07, 2017, 02:54:08 AM »

The general limitation on the pushing it hard part would be cooling, if I remember right.  There just isn't enough cooling to keep it going.
Logged
French G.
friend
Senior Member
***
Posts: 6,752


ohhh sparkles!


« Reply #3 on: December 07, 2017, 03:31:43 AM »

When I win Powerball it is either a Maule or an AN-2 for me.
Logged

AKA Navy Joe   

If you see ten threads coming down the road you can be sure nine will run into the ditch before you get a chance to post. I call that ditch APS. -Cal Coolidge
CypherNinja
friend
Member
***
Posts: 416



« Reply #4 on: December 07, 2017, 03:42:16 AM »

Typically it's a cooling limitation, the engine will overheat if operated at full power for too long. 100% for take-off, 75% or less for cruising is fairly typical.

In this case there's a little something extra going on, however.   Wink

Because the CarbonCub is a 'Light Sport Aircraft' category plane, they had to be super explicit in the specifications that the 'maximum cruise power' was only 80hp or so (Wink Wink Wink), and that you should never, ever, ever, ever, ever be above that for more than 5 mins. No matter what your temp gauge says. angel

Because LSAs are the 'more accessible' planes, they cant be to powerful don'tcha know?   cheesy
Logged

ôFear of death increases in exact proportion to increase in wealth,ö Hemingway once said. Today, many of us have become rich in the currency of cowardice. We have so many things and so few experiences. We are desperate to live as long as possible, not as large as possible. We are so afraid to say goodbye to the world that we never say hello.
-Marty Beckerman (from a Wired article of all things)
BobR
friend
Senior Member
***
Posts: 3,811



« Reply #5 on: December 07, 2017, 06:01:06 AM »

When I win Powerball it is either a Maule or an AN-2 for me.

It will be an AN-2 for me and I will spend the summer months lazily flying from one airshow to the next.  Smiley

bob
Logged
MillCreek
friend
Senior Member
***
Posts: 12,210


APS Risk Manager


« Reply #6 on: December 07, 2017, 06:06:16 AM »

http://www.heraldnet.com/business/chinese-firm-breaks-ground-on-arlington-plane-building-plant/

CubCrafters is building a factory in Arlington to build a SuperCub variant for the Chinese market.  I have already seen some aircraft in the local airport pattern as they come over from Yakima, where the main factory is.
Logged

_____________
Regards,
MillCreek
Snohomish County, WA  USA

I bear a passing resemblance to Squidward
Fly320s
friend
Senior Member
***
Posts: 9,722


If you can't get happy, get drunk.


« Reply #7 on: December 07, 2017, 06:39:27 AM »

The replies that mentioned engine life and maintenance are correct for most engine limitations, but not in this case.

The LSA rules don't limit engine horsepower, but they do limit maximum cruise speed to 138mph.  The engine in the Carbon Cub can produce 180hp, which is way more than other LSAs, but it is limited/derated to 80hp so as not to exceed the airspeed limitation.

So, you can have that 180hp for takeoff, but not for cruise.  The power is still there and available I assume, but you aren't allowed to use it.

Logged
230RN
friend
Senior Member
***
Posts: 9,781


I resent being prejudged as a racist.


« Reply #8 on: December 10, 2017, 11:46:49 AM »

OK, I think I get it.

Whether for mechanical cooling / engine running time / maintenance cycle limitations OR* for the sake of certain "class rules," the maximum power output** cannot be used for more than 5 minutes in this particular type of aircraft.

I guess the main problem for li'l ole groundlubber me was the sentence construction, since I had no background referents for the way it was stated.

Thanks, all. Smiley

Terry

* Not an exclusive "or."
** Or power output greater than the nominal 80 hp.
Had to look up Maule:
https://youtu.be/xK17ZY4ne40 (4:43 "Advertising")
« Last Edit: December 10, 2017, 12:15:05 PM by 230RN » Logged

When Democrats use the techniques they learned from Goebbels - was that cultural appropriation?
(With apologies to fistful.)
"Jerry... just remember... it's not a lie... if you believe it." --George Costanza.
(With thanks to George Costanza.)
Fly320s
friend
Senior Member
***
Posts: 9,722


If you can't get happy, get drunk.


« Reply #9 on: December 10, 2017, 12:00:39 PM »

Things get more complicated in multi-engine and/or turbine powered aircraft.

Some multi-engine aircraft have the 5 minute limitation for max power unless one engine has failed, then they get a 10 minute limitation.  That is an option that a manufacturer can pursue if they want.  Not all do.

Most turbine engines are built to produce much more power than the aircraft will need and then de-rated to a lower power limit.  For instance, the engines on my Airbus 320 are IAE-V2500 series.   The engines can produce 22,000 to 33,000 pounds of thrust, but ours are limited to 27,000 pounds of thrust.  We still have the 5 minute limitation on max power. 
Logged
230RN
friend
Senior Member
***
Posts: 9,781


I resent being prejudged as a racist.


« Reply #10 on: December 10, 2017, 12:03:11 PM »

^ Very interesting and informative example, thanks, Fly320s.  Smiley
Logged

When Democrats use the techniques they learned from Goebbels - was that cultural appropriation?
(With apologies to fistful.)
"Jerry... just remember... it's not a lie... if you believe it." --George Costanza.
(With thanks to George Costanza.)
Brad Johnson
friend
Senior Member
***
Posts: 12,915


Witty, charming, handsome, and completely insane.


« Reply #11 on: December 10, 2017, 01:13:02 PM »

Jeez... 180 HP in an airframe that light? You could damn near take off straight up.

Brad
Logged

It's all about the pancakes, people.
"And he thought cops wouldn't chase... a STOLEN DONUT TRUCK?Huh? That would be like Willie Nelson ignoring a pickup full of weed."
-HankB
230RN
friend
Senior Member
***
Posts: 9,781


I resent being prejudged as a racist.


« Reply #12 on: December 10, 2017, 01:37:41 PM »

Jeez... 180 HP in an airframe that light? You could damn near take off straight up.

Brad

I believe they call that "hanging on the prop."  I guess that depends on load.  I could swear I heard in one of the Maule videos that they could carry 2000 lb. of supplies.  Hmmmm Huh? ?
Logged

When Democrats use the techniques they learned from Goebbels - was that cultural appropriation?
(With apologies to fistful.)
"Jerry... just remember... it's not a lie... if you believe it." --George Costanza.
(With thanks to George Costanza.)
Fly320s
friend
Senior Member
***
Posts: 9,722


If you can't get happy, get drunk.


« Reply #13 on: December 10, 2017, 02:14:34 PM »

Maules are much bigger aircraft.  Still single-engine, but definitely not LSA.
Logged
KD5NRH
friends
Senior Member
***
Posts: 10,057


I'm too sexy for you people.


« Reply #14 on: December 10, 2017, 06:52:52 PM »

Jeez... 180 HP in an airframe that light? You could damn near take off straight up.

Comes in handy for carrier ops.  https://www.youtube.com/watch?v=V6nQw0a2Yq4
Logged
French G.
friend
Senior Member
***
Posts: 6,752


ohhh sparkles!


« Reply #15 on: December 10, 2017, 07:23:07 PM »

Thread drift, the F-14B and D were limited, supposedly the engines would be pushing well past where the airframe would fall apart.
Logged

AKA Navy Joe   

If you see ten threads coming down the road you can be sure nine will run into the ditch before you get a chance to post. I call that ditch APS. -Cal Coolidge
MillCreek
friend
Senior Member
***
Posts: 12,210


APS Risk Manager


« Reply #16 on: December 10, 2017, 07:40:54 PM »

Comes in handy for carrier ops.  https://www.youtube.com/watch?v=V6nQw0a2Yq4

So I wonder if he could have landed on the deck as well. I am not sure of the minimum landing distance for that airframe.
Logged

_____________
Regards,
MillCreek
Snohomish County, WA  USA

I bear a passing resemblance to Squidward
KD5NRH
friends
Senior Member
***
Posts: 10,057


I'm too sexy for you people.


« Reply #17 on: December 10, 2017, 07:51:52 PM »

So I wonder if he could have landed on the deck as well. I am not sure of the minimum landing distance for that airframe.

Barely, and not on the designated "runway" area; it needs 900' and the deck is 1000' total.

If the structure can take an arresting hook OTOH, then it's just a matter of adjusting the tension on the cables to not turn the pilot into paste.
Logged
230RN
friend
Senior Member
***
Posts: 9,781


I resent being prejudged as a racist.


« Reply #18 on: December 10, 2017, 11:03:26 PM »

^ "If the structure can take an arresting hook OTOH, then it's just a matter of adjusting the tension on the cables to not turn the pilot into paste."

gee whiz.

Thread drift, the F-14B and D were limited, supposedly the engines would be pushing well past where the airframe would fall apart.

OK for A and C, though, huh?  Actually, that's interesting.  And as the OP, I deem that OK.  Sorta like pushing a .220 Swift too fast.
« Last Edit: December 10, 2017, 11:18:22 PM by 230RN » Logged

When Democrats use the techniques they learned from Goebbels - was that cultural appropriation?
(With apologies to fistful.)
"Jerry... just remember... it's not a lie... if you believe it." --George Costanza.
(With thanks to George Costanza.)
Firethorn
friend
Senior Member
***
Posts: 5,158


Where'd my explosive space modulator go?


« Reply #19 on: December 10, 2017, 11:16:15 PM »

Barely, and not on the designated "runway" area; it needs 900' and the deck is 1000' total.

If the structure can take an arresting hook OTOH, then it's just a matter of adjusting the tension on the cables to not turn the pilot into paste.

Why that much?  No means of thrust reversal and limited braking power?
Logged
French G.
friend
Senior Member
***
Posts: 6,752


ohhh sparkles!


« Reply #20 on: Today at 04:10:56 AM »

^ "If the structure can take an arresting hook OTOH, then it's just a matter of adjusting the tension on the cables to not turn the pilot into paste."

gee whiz.

OK for A and C, though, huh?  Actually, that's interesting.  And as the OP, I deem that OK.  Sorta like pushing a .220 Swift too fast.
Well, complicated revision history. The Charlie was never really a thing and the Bravo almost wasn't many times, eventually becoming the designation of upgraded Alphas, or the A+ model
. The Delta was the one that was operational with the F101 engines and a 1:1 power to weight. Modern avionics and an upgrade program and we could still be flying. Expensive? Yep.  Compared to our aquisition boondoggles? Not so much. And we still don't have a capability like the AIM-54C.

Alphas were what I was around, did the last deployment of them in 1999, we had two A sauadrons on my ship. You could skate across bay three from all the oil. I didn't work direct support, I level, so fixed lots of tired parts. The best thing about the TF-30 engine in those was both of them still running at the end of the day.
Logged

AKA Navy Joe   

If you see ten threads coming down the road you can be sure nine will run into the ditch before you get a chance to post. I call that ditch APS. -Cal Coolidge
jamisjockey
Booze-fueled paragon of pointless cruelty and wanton sadism
Administrator
Senior Member
*****
Posts: 24,587


Your mom sends me care packages


« Reply #21 on: Today at 05:08:29 AM »

Jeez... 180 HP in an airframe that light? You could damn near take off straight up.

Brad

That's the point  laugh

https://youtu.be/--tmys3lnFY
Logged

JD

 "Why'd you open your bonghole, you smelly hippie? You'd sacrifice a beautiful woman to save a moderately attractive monkey? You must have smoked some bad granola."
dogmush
friend
Senior Member
***
Posts: 5,969


« Reply #22 on: Today at 05:27:09 AM »

That's the point  laugh

https://youtu.be/--tmys3lnFY

Meh.  The Aussies rolled for like three plane lengths.

This is how you do it:

https://youtu.be/gQJKW5vfvog?t=74
Logged
jamisjockey
Booze-fueled paragon of pointless cruelty and wanton sadism
Administrator
Senior Member
*****
Posts: 24,587


Your mom sends me care packages


« Reply #23 on: Today at 05:52:01 AM »

Meh.  The Aussies rolled for like three plane lengths.

This is how you do it:

https://youtu.be/gQJKW5vfvog?t=74

In a crosswind. 
Logged

JD

 "Why'd you open your bonghole, you smelly hippie? You'd sacrifice a beautiful woman to save a moderately attractive monkey? You must have smoked some bad granola."
Fly320s
friend
Senior Member
***
Posts: 9,722


If you can't get happy, get drunk.


« Reply #24 on: Today at 05:52:14 AM »

Meh.  The Aussies rolled for like three plane lengths.

This is how you do it:

https://youtu.be/gQJKW5vfvog?t=74

Give me a strong enough headwind and I can do that in my A320.
Logged
Pages: [1] 2
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!