Sport Pilot Talk

Daidalos · Joined: 12 Feb 2009 Posts: 135 Location: KHWV

Tecnam P20008 it says more information comming soon. Is it an LSA or not?

It's being advertised on Controller.

I hope the CSP members can elaborate.

drseti · Joined: 28 Nov 2009 Posts: 1384 Location: Lock Haven PA

According to the specs at http://www.pilotmix.com/index.php?pgid=11&lang=en&maxInfo=954, the cruise speed is listed as 122 kts. Since the LSA rules limit max cruise speed to 120 kts, I conclude that the P2008 would NOT qualify as LSA.

CharlieTango · Posted: Wed Jan 06, 2010 7:44 pm Post subject:

here's an article http://www.nac.co.za/articles.php?id=34 that says: "The TECNAM P2008 will be available in LSA, ULM, PtF and coming ELA1 categories."

Daidalos · Joined: 12 Feb 2009 Posts: 135 Location: KHWV

Here's an article from P&P March 30th, 2009 that says it's an LSA.

At the CSP open house I asked about the P2008 but did not receive a definitive answer.

They could have easily cut the speed from 122 to 120 knots with prop pitch. I'd like to see the W&B specs. It may be a direct competitor to the TL Sirius.

KSCessnaDriver · Joined: 25 Jan 2009 Posts: 159 Location: KOJC

Could it be that the plane can do 122 Knots Indicated, but yet only do 120 Knots Calibrated? Just thinking out loud, but its a possibility.

Daidalos · Joined: 12 Feb 2009 Posts: 135 Location: KHWV

KSCessnaDriver wrote: Could it be that the plane can do 122 Knots Indicated, but yet only do 120 Knots Calibrated? Just thinking out loud, but its a possibility.

I dooubt it. Have you ever looked at the AS indicator during stalls? The IAS is well below published Vs.

tadel001 · Joined: 12 Mar 2007 Posts: 251

The aircraft is an LSA. There should be one at Sebring. In fact, the first one arrives in Virginia this week.

CharlieTango · Posted: Thu Jan 07, 2010 10:15 am Post subject:

KSCessnaDriver wrote: Could it be that the plane can do 122 Knots Indicated, but yet only do 120 Knots Calibrated? Just thinking out loud, but its a possibility.

i noticed that they published

Cruise speed (75%, 6500 feet) 122 kts

Cruise speed (65%, 7500 feet) 116 kts

75% @ 6,500' would be close to wot @ 5,500 rpm and the speed would be True air speed.

this means that it isn't particularly fast. same settings and i see 125-130 tas.

drseti · Joined: 28 Nov 2009 Posts: 1384 Location: Lock Haven PA

CharlieTango wrote:
i noticed that they published

Cruise speed (75%, 6500 feet) 122 kts

That's what bothers me about the LSA claim. The regs require 120 kts max TAS at maximum continuous power. Seems to me, this plane exceeds that, if it can do 122 kts at 75%. So, how are they going to make the LSA spec?

CharlieTango · Posted: Thu Jan 07, 2010 11:20 am Post subject:

Actually the regs call for a max speed of 120kts CAS (calibrated air speed is same as indicated but adjusted for error)

If you can realize max speed (normally aspirated) on a standard day you would see 120kts @ sea level. At higher elevations up to 7,500' you will see a lower IAS but higher TAS.

Cold temps help as well, in the winter, even above @ 10,000' I see TAS well above 120kts.

If you had a 914 powered lsa and flew it to 17,000' you might be able to see 150kts and still be within the 120kt CAS limit.

KSCessnaDriver · Joined: 25 Jan 2009 Posts: 159 Location: KOJC

CharlieTango wrote: i noticed that they published

Cruise speed (75%, 6500 feet) 122 kts

Cruise speed (65%, 7500 feet) 116 kts

75% @ 6,500' would be close to wot @ 5,500 rpm and the speed would be True air speed.

this means that it isn't particularly fast. same settings and i see 125-130 tas.

Yes, but over the course of say a 300 mile trip, the difference is only a couple of minutes. Speed isn't everything to all buyers.

Murrell · Joined: 17 Feb 2006 Posts: 58

According to the specs at http://www.pilotmix.com/index.php?pgid=11&lang=en&maxInfo=954, the cruise speed is listed as 122 kts. Since the LSA rules limit max cruise speed to 120 kts, I conclude that the P2008 would NOT qualify as LSA.
_________________I have seen several sites that say the prop will be adjusted to comply with LSA speed requirements in the USA !

I would think LSA dealers would be aware of this.

Murrell

KSCessnaDriver · Joined: 25 Jan 2009 Posts: 159 Location: KOJC

Murrell wrote: According to the specs at http://www.pilotmix.com/index.php?pgid=11&lang=en&maxInfo=954, the cruise speed is listed as 122 kts. Since the LSA rules limit max cruise speed to 120 kts, I conclude that the P2008 would NOT qualify as LSA.
_________________I have seen several sites that say the prop will be adjusted to comply with LSA speed requirements in the USA !

I would think LSA dealers would be aware of this.

Murrell

Again, the 122 knots isn't listed as what kind of airspeed that is. It could easily be KIAS, while the 120 knot limit is KCAS (Knots Calibrated Airspeed). I would expect this to be the case, or Tecnam will surely either change the prop pitch, or add a small drag device somewhere on the wing.

bitten192 · Joined: 21 Dec 2009 Posts: 61 Location: RICHLAND WA USA

The 4 seat Jabiru has stops on the flaps so all the way "up" has a slight downward deflection which reduces the cruise speed to 120 kts. Not so in Australia.

eb

CharlieTango · Posted: Sat Jan 09, 2010 10:10 am Post subject:

KSCessnaDriver wrote: Again, the 122 knots isn't listed as what kind of airspeed that is. It could easily be KIAS, while the 120 knot limit is KCAS (Knots Calibrated Airspeed). I would expect this to be the case, or Tecnam will surely either change the prop pitch, or add a small drag device somewhere on the wing.

the reason the 122kt speed is qualified by 75% power and 7,500' is because that is where best speed is available and it is where only 75% power is available. True air speed is surely what they are referencing anything else would be a violation.

Assuming IAS would be assuming a lot of error and not plus or minus error only plus.

Limiting speed via prop pitch is a bad idea with a rotax because it viloates rotax's recommendations and leads to engine wear and early overhaul. Most designs will require compliance with rotax requirements. An exception would be to limit with a flat pitch as opposed to course but this would be prone to over speeding and therefore not a very workable technique to limit speed.

If the design is 122kts TAS at 7,500' at 75% (75% is wot @ 7,500') there is no need to limit the speed. the IAS / CAS would be under 110kts.

My numbers above are approximate and vary with conditions.