MOSAIC rule to be published on 7/24

Capt. Geoffrey Thorpe said:
edit:
Some models of Cessna 172 appears to squeak in by 1 knot other models do not. A more careful look is required...
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how is this all calculated? I don’t understand. I guess what I really want to know is if the artificial 1320 limit is going to be recalculated by a new formula or if the manufacturer will have it issue a change. From what I’ve seen, the 1320 limit is usually treated as “just a suggestion” by a lot of pilots, seeing what they haul into air shows.
 
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rhkennerly said:
how is this all calculated? I don’t understand. I guess what I really want to know is if the artificial 1320 limit is going to be recalculated by a new formula or if the manufacturer will have it issue a change. From what I’ve seen, the 1320 limit is usually treated as “just a suggestion” by a lot of pilots, seeing what they haul into air shows.
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It really depends on a plane - some planes were designed to higher gross and then designated and sold as LSA on the US market at 1320lbs gross - while not legal at least it would be reasonably sane to treat their gross as “just a suggestion” but if the plane was designed to 1320 lbs or so then that’s that.
 
DaleB said:
From what I can see, for airplanes the stall speed is going to effectively be the single limiting factor. If VS1 is that low, then it's going to meet all of the other criteria -- max number of seats, cruise speed, etc.

I know this is my disappointment with what happened with Basic Med raising its head, but I can't shake the feeling that after the comment period the max VS1 will get bumped down just enough to exclude 99% of the gains here... leaving us with slightly heavier variants of Champs, Chiefs, and Cubs. But that's just me being pessimistic.
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As written, this has the potential to save a lot of orphaned airplanes.
Kenny Phillips said:
The Vashon Ranger will go up to 1500 lbs as soon as the rule is in effect (per them, I asked about it.)
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I imagine they will not be the only ones. Several factory built LSA''s were shoehorned down slightly to meet the LSA/EASA rules.

Off the top of my head I can think of the Jabiru, Paradise/Texas Colt, and others. Especially those designed for the Eastern European markets like the Sportcruiser or Evektor.
 
DaleB said:
From what I can see, for airplanes the stall speed is going to effectively be the single limiting factor. If VS1 is that low, then it's going to meet all of the other criteria -- max number of seats, cruise speed, etc.

I know this is my disappointment with what happened with Basic Med raising its head, but I can't shake the feeling that after the comment period the max VS1 will get bumped down just enough to exclude 99% of the gains here... leaving us with slightly heavier variants of Champs, Chiefs, and Cubs. But that's just me being pessimistic.
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As written, this has the potential to save a lot of orphaned airplanes.
asicer said:
Perusing my collection of POH, DA40 made the cut but C177, AA5B, SR20 and M20 do not.
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This is going to breath new life into some lower end airplanes like the Traumahawk, Beech Skipper and Sundowner, both Commander Models Lark and Darter.

If this is accepted, I'm in the market for a Lark! (I have always wanted one)
 
Hey folks,

I think one critical aspect of the rule is if you can modify existing designs to get them to meet these new criteria as sport pilot eligible aircraft. Lots of existing aircraft have access to various STC based modifications that can get the vs1 calibrated down to these requirements. Unfortunately, you were not able to do this with the initial sport pilot rule - folks tried to lower the gross weight of Cessna 120s and 140s by STC to conform to sport pilot and the FAA nixed that.

Lots of planes are going to be within 3 or 4 knots of the rule - VGs for example can significantly lower these speeds through STC kits.
 
From what I can see, it looks like SPs can fly any 4 seat or less aircraft with 54 knots or less stall speed. The part about the aircraft continuously meeting the LSA limits since new seems to have gone away along with the Part 1.1 definition of light-sport aircraft.

Stall reducing STCs might become a profitable business for awhile...
 
rhkennerly said:
how is this all calculated? I don’t understand. I guess what I really want to know is if the artificial 1320 limit is going to be recalculated by a new formula or if the manufacturer will have it issue a change. From what I’ve seen, the 1320 limit is usually treated as “just a suggestion” by a lot of pilots, seeing what they haul into air shows.
Click to expand...
a paper regulatory change in weight doesn't not increase either useful load or structural integrity. It has to be the manufacturer changing limitations.
 
DFH65 said:
The manual for my 57 172 says:
TKOuJLH.jpg


Of course that is MPH :)
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There is a correction table, but it's indicated vs true. On yours, I'd go with sea level True as more likely right there with calibrated. Not that it matters at those speeds. :)

1689851871618.png
 
midlifeflyer said:
There is a correction table, but it's indicated vs true. On yours, I'd go with sea level True as more likely right there with calibrated. Not that it matters at those speeds. :)

View attachment 119159
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Notice that the table converts IAS to/from TIAS. I’m thinking that TIAS is an older term for CAS, not true airspeed.
 
When the regs say “VS1 speed of not more than 54 knots CAS”, I take the threshold to be 54.01. In other words “inclusive” of 54. Given this, and the reality of measuring precision, the actual threshold is 55 knots and above. If they had intended to include 54, the language would need to be different. So, if the number in the book or STC is 55 or more, you’re out. Splitting hairs, but sometimes hair needs to be split. Of course, the numbers may change in final rule.
 
MPB said:
Hey folks,

I think one critical aspect of the rule is if you can modify existing designs to get them to meet these new criteria as sport pilot eligible aircraft. Lots of existing aircraft have access to various STC based modifications that can get the vs1 calibrated down to these requirements. Unfortunately, you were not able to do this with the initial sport pilot rule - folks tried to lower the gross weight of Cessna 120s and 140s by STC to conform to sport pilot and the FAA nixed that.

Lots of planes are going to be within 3 or 4 knots of the rule - VGs for example can significantly lower these speeds through STC kits.
Click to expand...

Dana said:
From what I can see, it looks like SPs can fly any 4 seat or less aircraft with 54 knots or less stall speed. The part about the aircraft continuously meeting the LSA limits since new seems to have gone away along with the Part 1.1 definition of light-sport aircraft.

Stall reducing STCs might become a profitable business for awhile...
Click to expand...
61.316 (a)"[...] you may act as pilot in command of an aircraft that, since its original certification, meets the following requirements:"

Geoff "Wet Blanket" Thorpe.
 
rhkennerly said:
how is this all calculated? I don’t understand. I guess what I really want to know is if the artificial 1320 limit is going to be recalculated by a new formula or if the manufacturer will have it issue a change. From what I’ve seen, the 1320 limit is usually treated as “just a suggestion” by a lot of pilots, seeing what they haul into air shows.
Click to expand...
One would assume that the stall speed would be measured by flight testing. (There is no gross weight limit in the new rules.)
One issue for legacy aircraft could be that the clean (flaps up) stall speed might not be listed in the manual or may be in indicated airspeed, not calibrated. Some detective work may be required.
Of course, this is similar to the current limit on top speed (which is not longer a limit on what a sport pilot may operate): "A maximum airspeed in level flight with maximum continuous power (VH) of not more than 120 knots CAS under standard atmospheric conditions at sea level." You won't find that number in the manual for legacy aircraft either. For something like a Cub, it's obvious that it's going to be well under 120 knots, but I'm sure there are a lot of edge cases.

Exceeding the manufacturers recommended maximum weight is not that uncommon - and not just limited to LSAs. Not necessarily a good idea, but it happens. And yes, for, say, a 172, flying heavier than gross could push the actual stall speed over yea olde 54 knot CAS. I guess some pilots are just bad people.
 
Capt. Geoffrey Thorpe said:
61.316 (a)"[...] you may act as pilot in command of an aircraft that, since its original certification, meets the following requirements:"

Geoff "Wet Blanket" Thorpe.
Click to expand...
Right, I missed that. Really a stupid requirement (send those comments in!).
 
Tspin said:
Notice that the table converts IAS to/from TIAS. I’m thinking that TIAS is an older term for CAS, not true airspeed.
Click to expand...

midlifeflyer said:
I'm thinking the manual tells us what it is

View attachment 119160
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Mark, it's still not clear what is meant by "true indicated airspeed". In today's terminology, it's either "true airspeed" or "indicated airspeed". "True indicated airspeed" is a contradiction. Kind of like "real imitation crab meat".

Is there another section in the book that defines terms? Because my first thought was like @Tspin 's, where "true indicated" means "accurately corrected indicated", which says to me "calibrated".

Or it's possible, of course, that "indicated" is an extraneous word. Or it's possible that back in 1957 the terms weren't defined the same as today. Or several other scenarios.
 
Warmi said:
Pretty much the same at MSL..
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At higher speeds, yes, but not at the lower speeds and therefore higher AOAs that are required to stall the airplane. I've flown planes before that indicated <20 knots before they stall. These would be planes like a 182, not some STOL-competition airplane. Clearly our CAS was way more than that. The angle of the pitot tube at those AOAs interferes with air flow into the tube and therefore into the airspeed indicator.
 
Warmi said:
It really depends on a plane - some planes were designed to higher gross and then designated and sold as LSA on the US market at 1320lbs gross - while not legal at least it would be reasonably sane to treat their gross as “just a suggestion” but if the plane was designed to 1320 lbs or so then that’s that.
Click to expand...
Oh, okay. I thought by what you said about the 172 that you pulled out some formula that I just couldn’t see in the regs. Glad to know I can still read. Tnx.
 
Capt. Geoffrey Thorpe said:
Exceeding the manufacturers recommended maximum weight is not that uncommon - and not just limited to LSAs. Not necessarily a good idea, but it happens. And yes, for, say, a 172, flying heavier than gross could push the actual stall speed over yea olde 54 knot CAS. I guess some pilots are just bad people.
Click to expand...

I was thinking about planes like the Jabaru, in particular. the J is sold as an LSA in the US but a 3 place plane in Australia. For the US market they took the backseat out, which leaves a baggage area big enough to sublet as an apartment.
 
rhkennerly said:
I was thinking about planes like the Jabaru, in particular. the J is sold as an LSA in the US but a 3 place plane in Australia. For the US market they took the backseat out, which leaves a baggage area big enough to sublet as an apartment.
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Presumably, you could increase the gross on something like the Jabaru to match the European number - but I have no idea what kind of paperwork that would involve. For an E-AB (say, a SeaRey) I would assume that it would be considered a major alteration and you would go back into phase 1. But for S-LSA or E-LSA the FAA has separated out the requirements for certificating the aircraft from the definition of what a Light and Sporty Guy can fly, and I have not looked into those details (which are likely to change by the time the rule comes out for real).
 
rhkennerly said:
Oh, okay. I thought by what you said about the 172 that you pulled out some formula that I just couldn’t see in the regs. Glad to know I can still read. Tnx.
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Just trying to look up stall speeds for 172s - there appears to be some variation based on model, but some of that may be due to IAS vs CAS? Changes in gross weight? Just bad information on the web?
 
Baked Potato said:
Yep... Apologies to flying club members with a PPL, but I am coming for your Cessnas. And there's nothing that can stop me
(except a multi-year waiting list and voting approval from 2/3 of the current membership)
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Bring lots of cash..
 
Warmi said:
if the plane was designed to 1320 lbs or so then that’s that.
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My ride is (per the kit manufacturer) 1300 gross on wheels, 1400ish on floats. So one would think that the wings are not going to fall of at 1400 pounds. Assuming that Mosaic is actually similar to what is proposed and is implemented in my lifetime - To do, or not to do, that is the question.
 
For those who don't want to read the whole thing, these are the important bits:

The new part 22 defines what can be certificated as a Light-Sport Aircraft:

Subpart B – Light-Sport Category Aircraft
§ 22.100 Eligibility.
(a) Aircraft manufactured in the United States. To be eligible for a special
airworthiness certificate in the light-sport category issued under § 21.190 of this chapter,
an aircraft must –
(1) Except for an airplane, have a maximum seating capacity of not more than two
persons, including the pilot.
(2) For an airplane, have a maximum seating capacity of not more than four
persons, including the pilot.
(3) Have a maximum stalling speed or minimum steady flight speed, without the
use of lift-enhancing devices (VS1) at the aircraft's maximum certificated takeoff weight
and most critical center of gravity of 54 knots CAS for an airplane, or 45 knots CAS for a
glider or weight-shift-control aircraft.
(4) Have a maximum speed of 250 knots CAS at maximum available power under
standard atmospheric conditions at sea level.
(5) Have a non-pressurized cabin, if equipped with a cabin.
(6) Not have been previously issued a standard, primary, restricted, limited, or
provisional airworthiness certificate, or an equivalent airworthiness certificate by a
foreign civil aviation authority.
(7) Meet the aircraft design, production, and airworthiness requirements specified
in this subpart using a means of compliance consisting of consensus standards accepted
by the FAA.
(8) Be inspected by the FAA and found to be in a condition for safe operation.
(b) Aircraft manufactured outside the United States. For aircraft manufactured
outside the United States to be eligible for a special airworthiness certificate in the lightsport
category under § 21.190 of this chapter, an applicant must provide the FAA
evidence that—
(1) The aircraft meets the requirements of this subpart;
(2) The aircraft was manufactured in a country with which the United States has a
Bilateral Airworthiness Agreement concerning airplanes or Bilateral Aviation Safety
Agreement with associated Implementation Procedures for Airworthiness concerning
airplanes, or an equivalent airworthiness agreement; and
(3) The aircraft is eligible for an airworthiness certificate, flight authorization, or
other similar certification in its country of manufacture.

Part 61 defines what types of aircraft a Sport Pilot can fly, regardless of how the aircraft is certificated:

§ 61.316 What are the performance limits and design requirements for the aircraft
that a sport pilot may operate?
(a) If you hold a sport pilot certificate, you may act as pilot in command of an
aircraft that, since its original certification, meets the following requirements:
(1) A maximum stalling speed or minimum steady flight speed without the use of
lift-enhancing devices (VS1) of not more than 45 knots CAS, except for airplanes, which
must have a VS1 speed of not more than 54 knots CAS at the aircraft’s maximum
certificated takeoff weight and most critical center of gravity.
(2) A maximum seating capacity of two persons, except for airplanes, which may
have a maximum seating capacity of four persons.
(3) A non-pressurized cabin, if equipped with a cabin.
(4) For powered aircraft other than powered gilders, a fixed or ground-adjustable
propeller, except as provided in paragraph (b) of this section.
(5) For powered gliders, a fixed or feathering propeller system.
(6) For gyroplanes, a fixed-pitch, semi-rigid, teetering, two-blade rotor system.
(7) For powered aircraft other than balloons or airships, the loss of partial power
would not adversely affect directional control of the aircraft and the aircraft design must
allow the pilot the capability of establishing a controlled descent in the event of a partial
or total powerplant failure.
(8) For helicopters, they must be certificated with the simplified flight controls
design and designation.
(9) For a glider, fixed or retractable landing gear.
(10) For an aircraft intended for operation on water, fixed or retractable landing
gear or a hull.
(11) For powered-aircraft other than a glider or an aircraft intended for operation
on water, fixed landing gear except as provided in paragraph (b) of this section.
(b) If you hold a sport pilot certificate, you may act as pilot in command of an
airplane that, since its original certification, has retractable landing gear or a controllable
pitch propeller if you have met the training and endorsement requirements specified in
§ 61.331.
 
Well, the RV vs Zenith decision just got much easier.

Now, where to build....
 
Capt. Geoffrey Thorpe said:
As currently proposed, the weight limit is replaced with:
"A maximum stalling speed or minimum steady flight speed without the use of
lift-enhancing devices (VS1) [...] for airplanes, which
must have a VS1 speed of not more than 54 knots CAS at the aircraft’s maximum
certificated takeoff weight and most critical center of gravity."

Which may or may not correspond to about 3000 pounds.
Wing area will have a big impact on weight vs. stall speed.


edit:
Some models of Cessna 172 appears to squeak in by 1 knot other models do not. A more careful look is required...
Click to expand...
Crap....VS1 on my cherokee 180 is 58 kts.
 
bflynn said:
Well, the RV vs Zenith decision just got much easier.

Now, where to build....
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I was thinking the market price for RV-9s may rise.

Seems to me RV-7s etc may be right on the edge but Vans doesn't publish the no-flap stall speed.
 
Tusayan said:
I was thinking the market price for RV-9s may rise.

Seems to me RV-7s etc may be right on the edge but Vans doesn't publish the no-flap stall speed.
Click to expand...

Want to bet they do by the end of the show? The 58 they show is mph, so 50 kts.

I suppose you could write the aoh to prohibit landings without flaps, so Vso is 50.
 
Capt. Geoffrey Thorpe said:
61.316 (a)"[...] you may act as pilot in command of an aircraft that, since its original certification, meets the following requirements:"

Geoff "Wet Blanket" Thorpe.
Click to expand...
That's why you can have a 100% stock Taylorcraft, but it's not legal because someone back in the day put a Beech Roby in-flight adjustable prop on it even though it's looooong gone. Ask me how I know.
 
bflynn said:
I suppose you could write the aoh to prohibit landings without flaps, so Vso is 50.
Click to expand...
That changes the landing procedure but does not change the "maximum stalling speed or minimum steady flight speed without the use of lift-enhancing devices (VS1)".
 
bflynn said:
What year? Mph or kts?
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180D, 1969, 58 kts

On the other hand, I wouldn’t change to MOSAIC, because I usually have a parent in the back seat for Young Eagles.
 
Tusayan said:
Seems to me RV-7s etc may be right on the edge but Vans doesn't publish the no-flap stall speed.
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My guess is that Van's will soon publish the clean stall speed and that they will qualify ... ;)
 
MPB said:
Sport pilot instructors should not be teaching outside of traditional sport pilot aircraft - enough said there - if they want to teach at a higher level they should become CFIs.
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No, not enough said there. What makes a CFI-SP unqualified to teach in the expanded envelope, and what makes a CFI not a CFI?
 
Baked Potato said:
Correct me if I'm wrong, but I don't think it makes a difference. Vs1 is just in clean configuration.
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From a numbers perspective, there can be a significant difference. The difference is close to 5 knots in my RV-10.
 
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