Veloce 600, 6 seat pressurized twin auto-converted engines.

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Alessandre

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I got surprised with this model that I occasionally saw in my facebook today, this is a new model with twin aeromomentum engines:

PRESSURIZED VELOCE 600 TWIN – Aeromomentum 260 HP / TIO-540 270 HP

Cruise speed35,000 ft302 knots35,000 ft302 knots
Stall Speed57 knots w/flaps69 knots w/o flaps59 knots w/flaps71 knots w/o flaps
Climb Rate2285 ft/min1 engine 1020 ft/min2200 ft/min1 engine 1000 ft/min
Range2289 NM IFR w/R1950 VFR2100 NM IFR w/R1850 VFR
Take Offover 50 foot1130 ftover 50 foot1280 ft
Landingover 50 foot1120 ftover 50 foot1360 ft
Empty Weight2200 lbs2600 lbs
Useful Load1600 lbs1200 lbs
Wingspan35.5′35.5′
Length27′27′
High9.9′9.9′
Kit Cost$100,000 – show special$100,000 – show special

1629995752263.png

In my opinion 2 auto-converted engines could solve the issue of less reliability of the auto converted engines keeping their low maintenance cost.

From facebook publicity:
"Want a 6 seat pressurized plane that does 302 KTS at 35,000 ft or 270 kts at 25,000 ft, burning 22 GPH of AV or MOgas for $220k all in if you build yourself in 1200 hours.
$220k your cost all in for engines, avionics, interior, gear, and kit? You assemble in about 1,200 hours. Kit is $100k for composite parts (full list of prices for what is needed below)
Or fully completed ready to fly for $500k with really nice options.
Electric de-ice, AC, Garmin dual glass panel suite and auto pilot, custom paint job of your choice, custom interior of your choice, and more.
Basically a cirrus jet – for $500k instead of 2.5M (but 6 inches smaller on the inside)
And not something in theory, or maybe one day type plane from a new company.
But a company already in production that has already completed 2 other planes that are flying.
Already 107+ of the lineage planes flying from this company– with 7 of the 400 model flying in brazil.
First 600 will be flying within 10-12 months.
Introducing for the first time ever - anything like it at all for the price . . .
Veloce 600 - twin 6 place pressurized 520 HP plane."

In a quick survey I figured out that is a company from Brazil that has produced and flew 2 more models.

Veloce 400

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Veloce 200

1629996148543.png
 

rv6ejguy

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The performance specs seem pretty optimistic. Not going to go 300 knots on 22 gph IMO. Climb at 1000 fpm on one engine with apparently FP props? Electric de-ice with piston engines and alternators- hmmm not with a composite structure unless electro-pulse type which isn't cheap and needs aluminum skins to my knowledge. Probably not going to weigh only 2200 pounds empty either with at least 600 pounds of powerplant weight here.

Why don't designers wait until the prototype flies before releasing numbers? Neither of these engines are proven to fly at 35,000 feet. That's a tall order if you've never done it before.

Range doesn't add up with 6 aboard, baggage etc. At most, 3 hours of fuel at 22 gph, 900 NM. Maybe with 2-3 people aboard.

Edit: It seems Mark from Aermomentum designed this plane. I respect Mark but don't believe these projected numbers will be anywhere close to actual ones. That WOULD be a revolution if it does. Wish Mark the best on this project anyway and hope he proves me wrong.
 
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Alessandre

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The performance specs are nonsense. Not going to go 300 knots on 22 gph. Not going to climb at 1000 fpm on one engine. Electric de-ice with piston engines and alternators- nope, especially not with a composite structure. Not going to weigh 2200 pounds empty either.

Why don't they wait until the prototype flies before opening their mouths. Neither of these engines are proven to fly at 35,000 feet.

Range doesn't add up with 6 aboard, baggage etc. At most, 3 hours of fuel at 22 gph, 900 NM. Maybe with 2-3 people aboard.
I didn't pay attention for these numbers, 2200 lb empty minus the engines weight means 1570lb of fuselage for 6 people, I'm curious for see the real numbers.
35000 ft looks unreal for piston propelled aircraft :fear:. Would be this the finally revolutionary experimental aircraft?

The raptor aircraft was promising fly 25k pressurized, I never saw it flying over 5k.
 

blane.c

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Aeromomentum has 260hp turbocharged engines if memory serves, they likely will not put out that much power for much altitude, that is I don't know how much if any pressure is being waste gated at sea level. But being optimistic say they can maintain for maybe 12,000ft or so that still leaves 23,000ft for them to drop hp at a rate approximating 3% per thousand or a hp loss of 69% so how fast is this thing at sea level with 31% power 80hp x 2 engines 160hp? 302knots at 35,000ft is about 178knots at sea level and it has to do it on 160hp or likely less, then there is propeller efficiency and whether the engine will even run efficiently at that power level and altitude, remember outside air temperature up there is going to be something like 40 below zero your choice F or C which effects engine performance and you want it to put out enough extra heat for the heater to work.
 

rv6ejguy

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I might add that this would need a 7 to 8 psi cabin differential at 35K. Good luck with that using the windshield and windows shown in the render. The small aspect ratio wing won't be cruise friendly up there and I see nowhere near enough inlet area to dissipate the cooling/ intercooling loads up there. I calculate a pressure ratio of 5-6 required for 75% power at FL350, that means 2 stage turbos. Pretty sure AM hasn't tested such an engine and certainly haven't flown any up there.
 
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Alessandre

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Performance number from their website:

Cruise Speeds with Aeromomentum / all less with TIO-540
@6,000 @75% power230 knots burning 25gph
@18,000 @65% power240 knots burning 22gph
@25,000 @65% power270 knots burning 22gph
@34,000 @65% power302 knots burning 22gph
STALL SPEEDCLIMB RATE
57 knots w/flaps2285 ft/min
69 knots w/o flaps1 engine 1020ft/min


VFR Range
@18,000 @65% power248knots burning 22gph1233nm
@18,000 @55% power235knots burning 18.6gph1400nm
@18,000 @45% power220knots burning 15.2gph1625nm
@18,000 @35% power202knots burning 12gph1950nm


IFR Range W/Reserves
@35,000 @65% power302knots burning 22gph1410nm
@35,000 @55% power288knots burning 18.6gph1615nm
@35,000 @45% power269knots burning 15.2gph1890nm
@35,000 @35% power248knots burning 12gph2289nm

1630000750534.png
 

zolotiyeruki

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Paging @aeromomentum since he often hangs out around here.

I actually talked to Mark at Oshkosh about it. IIRC, there are cooling inlets on the underside of the negine nacelles. I don't know enough to comment on whether the numbers make sense, so I won't. The engines are 2.0L turbo charged Hyundai engines, but Aeromomentum's agreement prohibits them from uttering the H word. :)

The web page for the 600 is here: Veloce 600 – Veloce Planes
 

aeromomentum

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I might add that this would need a 7 to 8 psi cabin differential at 35K. Good luck with that using the windshield and windows shown in the render. The small aspect ratio wing won't be cruise friendly up there and I see nowhere near enough inlet area to dissipate the cooling/ intercooling loads up there. I calculate a pressure ratio of 5-6 required for 75% power at FL350, that means 2 stage turbos. Pretty sure AM hasn't tested such an engine and certainly haven't flown any up there.
The windshield will be different than the rendering but keep in mind that there are actually a lot larger plexiglass canopies on pressurized aircraft that fly at a much higher altitude. The key is to keep the load in tension and not bending.

Not sure about the rendering but the AR is 9. But as everyone knows, for induced drag it is span loading and not AR that matters. At times you may want to make the wing with more cord for structural, fuel capacity, stall speed and for other reasons. Like just about all GA aircraft the wing is larger than optimum for cruise but the wing size is more controlled by other parameters.

The projected maximum power at 35k is 65% and not 75%. We are not currently testing the AM20T at this altitude/power with the current turbo but we have investigated a different and larger single stage turbo that should be able to provide the needed pressure ratio. There are some certified aircraft with single stage turbos that have ceilings over 30k so we are not pushing the limit by a large amount.

As a comparison point, the 3550 lb Lancair IVP could cruise at 291knots at 24k and 75% of the 350hp burning about 17-18gph. Two AM20T's are about 100 lbs more than the single TSIO-550 as used in the Lancair IV. So even if we have learned nothing in the last 30 years, we should be able to have a 2300 lbs empty weight. But we have learned a little so saving just 100 lbs is possible to meet the 2200 lb target weight.

For example on an LSA that I designed and has flown, I saved over 50% of the weight of the control systems partly by using double taper carbon fiber control tubes instead of constant section aluminum control tubes. On a plane the size of the Veloce just this is about 20 lbs so about 20% of the required weight savings to meet the empty weight goal. On another LSA I saved over 50% on the landing gear weight by going from an aluminum one piece main gear leg to a 2 piece fiberglass gear leg and to a fiberglass nose gear. The original gear structure was about 40 lbs total. So about 20 lbs savings on an LSA or about 50lbs savings if scaled for the Veloce. So now with careful engineering we can save 70 lbs just on the control system and landing gear. The fully circular fuselage cross section also has weight savings over the rounded rectangular cross section of the Lancair IV in a pressurized aircraft.

There is really nothing "revolutionary" about the claims. It is really evolutionary and everything is within the limits of current engineering.
 

nicknack

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It will interesting if this airframe gets proven with whatever piston engine available and then a reliable “affordable” turboprop like the turbaero or pbs TP100 is adapted for the airframe. This plane will then look a lot like a avanti piaggio. A twin turboprop with de ice and usable range and pressurization at $300 to $500k is a steal. In absolute price it’s not cheap but relative to its class it’s cheap. However to fly at FL270 and above most likely this plane may need to be certified for RSM(reduced separation minimums)
 

aeromomentum

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The performance specs seem pretty optimistic. Not going to go 300 knots on 22 gph IMO. Climb at 1000 fpm on one engine with apparently FP props? Electric de-ice with piston engines and alternators- hmmm not with a composite structure unless electro-pulse type which isn't cheap and needs aluminum skins to my knowledge. Probably not going to weigh only 2200 pounds empty either with at least 600 pounds of powerplant weight here.

Why don't designers wait until the prototype flies before releasing numbers? Neither of these engines are proven to fly at 35,000 feet. That's a tall order if you've never done it before.

Range doesn't add up with 6 aboard, baggage etc. At most, 3 hours of fuel at 22 gph, 900 NM. Maybe with 2-3 people aboard.

Edit: It seems Mark from Aermomentum designed this plane. I respect Mark but don't believe these projected numbers will be anywhere close to actual ones. That WOULD be a revolution if it does. Wish Mark the best on this project anyway and hope he proves me wrong.
Yes it will go 300 knots on 22gph. Case in point, the similar weight Lancair doing 291 knots on 17-18gph.
The props will be constant speed and we have been talking with a few manufacturers.

As the designer, I did not release any numbers. That was the marketing person.

Initial engines/turbo are to max performance cruise power at 24kmsl like most turbocharged aircraft. But engineering data looks like 35k is about the limit with these engines and single stage large turbos.

Like almost all (every?) aircraft, the maximum range is at reduced payload and at an economy cruise not max performance cruise.
 

Vigilant1

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The projected single engine climb rate is 45% of the projected two engine climb rate. Is there another existing twin that can do this? The implication is that this design, at its 3800 lb MTOW, requires only 2.5% of the installed power (about 13hp) to achieve level flight at Vy and also that single engine asymmetrical trim drag will be very small.
 
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tspear

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Mark,

We talked about this design a number of years ago. Nice to see you are finally going to make it happen.

Tim
 

aeromomentum

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The projected single engine climb rate is 45% of the projected two engine climb rate. Is there another existing twin that can do this? The implication is that this design, at its 3800 lb MTOW, requires only 5% of the installed power (about 26hp) to achieve level flight at Vy and also that single engine asymmetrical trim drag will be very small.
The 1020 ft/min single engine climb is what I calculated. The two engine rate of climb should be about 2850 ft/min. I think the 2285 was a typo. So this is about 10.5% of the installed power (55hp) to maintain level flight at best L/D. This is not uncommon for a very clean high installed power aircraft. I did not take into account the drag of a feathered prop or the trim drag. Yes, there is less asymmetrical thrust than conventional light twins due to reduced prop spacing.
 

aeromomentum

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I very much like the comments and am open to criticism! Hopefully constructive. I would rather find flaws now than during flight test. I also do not mean to come across as a know it all defensive or over confidant in my design/calculations. I have been working on this design for some time and have had a few other engineers look over my work and provide useful changes but no one can think of everything or be right all the time.
 
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