Turbulence: PA28 vs Pipersport

[reimomo]

I've been flying a Warrior for the last 5 years and been perfectly happy with it, but in common with many on this board I've been contemplating alternatives to try and mitigate the constant fuel price hikes. The LAA/permit/mogas types appeal to me: I don't really need 4 seats and whilst I have an IMC I'm not hell-bent on keeping the capability.

I'd had an eye on the Pipersport. Nice lines, solid brand, great visibility so I went up for a demo flight. I've very limited type experience, having passed my PPL in a 152 and moved on to a Warrior. Clearly even with my limited knowledge one would expect a lightweight 2-seater to move around more than a Warrior, but I was surprised by the difference. I soon wasn't feeling great, and I'm not normally bothered by a bit of turb. The demo pilot passed this off as a breezy day with plenty of warm thermals at 1000-2000ft. Maybe, but we'd just flown up there in a Warrior and had hardly noticed the weather.

It was a real shame. I loved the idea of the plane, but I couldn't risk taking a friend up in it on a typical summer day without fear of them throwing up. Or me, for that matter.

So my question is:

Is it the case that all lightweight permit types suffer from increased turbulence and one either puts up with it or sticks with a CAA workhorse?

Or is the Pipersport a notorious poor performer in this regard? I'd read somewhere that it's 'wing-loading figure' was a contributory factor. Are there lightweight permit aircraft that are more forgiving? How about the MCR01, a Vans or a Jodel? Is there a wing-loading figure that's quoted in specs which will shed some light on likely buffeting? Or is it simply a case of trying all of them?!

Any advice, anecdotal or otherwise gratefully received.

[IO540]

Suspectibility to turbulence is directly related to wing loading. Low WL = you get chucked around more.

The stall speed is also largely related to wing loading. If you want a low Vs, then (setting aside some drastic measures like leading edge slats) you will have a low WL.

And, given that one is always power (i.e. acceleration) limited, the only way to get a short field performance is to have a low Vs.

So, all the "slow", short field capable, etc, types will get chucked around.

If you want a firm ride, you need to go for a plane which has a higher Vs. I don't recall the Vs of a PA28 (50kt?) but my TB20 has a Vs of 60kt which is just 1kt below the maximum allowed for a single engine plane. And it has a higher WL than most types with the same Vs. And it has a very good ride; nobody I know of has ever been sick in one.

This is one of many compromises...

[Rod1]

The Piper sport has an unusually low wing loading compared with the P300 or MCR01. It is much more susceptible to turbulence. IO540’s assertion that you need a high stall speed forgets that with modern aerodynamics you can make Flaps which are much more effective than the common older designs. My MCR has slats built into the flaps and that allows a low stall speed (along with light weight) of 42kn and good short field performance. In an MCR you do have to slow down in turbulent air, maybe going for 128kn, or in extreme conditions 115kn.

If you want to come up to the midlands I will give you a ride.

Rod1

[A and C]

I would agree with Rod & IO540 on the wing loading issue, however the aircraft is very light in the pitch control and this is likely to result in PIO for someone with the background discribed.

An hour or two with an instructor will sort out the PIO that is likely to be induced by any one new to the type.

[rkgpilot]

I've been thinking about a lower-cost option for flying too, and have been thinking about a Jabiru SK2200.

Anyone here know what they are like in turbulence/crosswinds?

[Cows getting bigger]

Jabs aren't great with crosswinds at lower speeds (ie with flap down). The flaps blank the airflow from a significant portion of the fin. Good cruising machines, but a bit 'sloppy' when landing.

[reimomo]

Ok, so it's wing loading as much as low Vs - thanks for that. How does one find that out? Is there a maths formula?

I've no big need for short strips, or energetic air manoeuvres. I'm just looking for something that will happily sit at 100knts or thereabouts without spending a £60-odd an hour just on gas (which is being burnt simply to keep an heavy, mostly empty airframe airborne).

Rod, thanks very much for your offer. I've seen a few MCRs in ads and I'm intrigued.

A & C, as I understand it the Pipersport is a newer version of the Czechsport, and the overly sensitive pitch control was supposedly corrected in the transition. What's 'PIO'?

[Jan Olieslagers]

Agreed to windloading being the main issue, but isn't turbulence worse in a lighter craft anyway?

As for the Jabiru ultralights: there used to be a J450 at my then home airfield, it had a very poor crosswind reputation.

[englishal]

Ok, so it's wing loading as much as low Vs - thanks for that. How does one find that out? Is there a maths formula?

Surface area of the wing divided by the max weight or something like that.

I've heard this criticism of the Sport Cruiser before, and I was surprised when someone mentioned to me that their Rallye they used to fly was much less affected by turbulence than their SC.

[gasax]

The majority of LSA types will suffer the same effect. Rod1's machine is a little different because of the comparatively tiny wing and clever flaps.

My Zodiac 601xl has essentially the same dimensions as the Sport Cruiser and yes you do need to slow down in turbulence. In rough turbulence the light pitch forces need care otherwise it can be quite easy to makes things worst.

It would be nice to have a more comfortable ride - but then I would loose the excellent strip performance. As with all things flying there are compromises that have to be made.

[hatzflyer]

PIO is pilot induced oscilation.
All lighter aircraft will suffer more from turbulance, watch all the microlight boys, they suffer the most but to their credit it doesn't seem to stop them doing some pretty impressive trips.Most of them fly more cross country than the average G.A. renter but they do seem to cruise at greater heights where they can.

Also don't rule out some of the older LAA (PFA) types, whilst not quite as quick or frugal as the modern Rotax 4 stroke types, the purchase costs are significantly less and the balance will pay for many years of flying.My Minicab lifts two largish people, cruises at 90/95 knots at 18lts/hr. Its short field, long range ,lovely handling, not overly bothered by turbulance and there are a couple for sale at the moment at about £10k. Highly recommended.

[Rod1]

This is a post I put together some time ago, you will see that the PiperSport (SC) is the heaviest aircraft but has a much lower wing loading than the comparison machines;

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Comparing aircraft numbers is an interesting pastime and can be useful to sort the facts from the fiction. The Sportcruiser was designed to meet the US LSA cat, but most of the SC aircraft in the UK are flying based on compliance with CS-VLA. If we compare the SC with other VLA machines we get some interesting results;

“The aircraft is very light (~380kgs Empty mass, 600kgs MAUW)”

Compared with a 152 (1950’s tec) it is light, compared with the modern VLA designs it is very heavy. This is probably due to the use of traditional metal construction. Some comparisons;

SC 380kg
Pioneer 300 305kg
MCR01 Club 250kg

All three use the same Rotax 912 100hp engine, so the power to weight ratio is very different, which of course has a big impact on performance;

SC Cruise 105 kts ~ 18 lts/hr
Pioneer Cruise 135 kts ~ 18.5 lts/hr
MCR01 Club Cruise 138 kts ~ 18.5 lts/hr

So the aircraft is about 40% slower. This of course will mean you need a lot more fuel to travel the same distance, so can the CS carry the extra fuel?

SC 120L
Pioneer 80L
MCR01 80L

So the lack of speed can be compensated by fuel capacity, but can it lift the weight?

SC 220kg
Pioneer 201kg
MCR01 Club 240kg

Certainly any advantage of the fuel capacity is seriously compromised by the speed / load equation. How Comfortable? The SC is a much bigger aircraft than the others, so what about cockpit width?

SC 46.5”
Pionear 41.3”
MCR01 44.5”

A clear win for the SC, but there is another issue with how Comfortable an aircraft is. How much do you get bounced around on an average UK summers day? This is not just about weight; it is also about wing area;

CS 13.2 Msq
Pioneer 10 Msq
MCR01 6.5 Msq

The key issue being wing loading;

CS 45 kg/sq
Pioneer 56 kg/sq
MCR01 75 kg/sq

Of all the aircraft above, the SC is the most likely to have to slow down in turbulence, but does the large wing give it an advantage in stall speed?

SC 38kn
Pioneer 44kn
MCR01 42kn

So a clear win for the SC, which should allow it to use a bit less runway; I cannot find a full set of figures on that, but it is almost certainly true.

Crosswind limit?

CS Anyone?
Pioneer 20kn
MCR 20Kn

Rate of Climb?

CD 1200 fpm
Pioneer 1500 fpm
MCR01 1600 fpm

Certification limitations?

All the above are VFR only no hire allowed. All are working on factory built aircraft certification with an eye on the training and private owner market, but the VFR restriction will stay. The CS is at least six months ahead of the mcr01 on this and I have no up to date Info on the Pioneer.

Conclusion

Unless you are talking solely of replacing the 152 fleet, the CS should be compared with other similar aircraft, which are available in Europe. My analysis is incomplete, and only covers aircraft, which I had figures to hand. Personally I would find the speed issue with the SC an impossible pill to swallow. I often fly 2 / 3 two hour legs in a day when I am in serious touring mode. The 40% increase required for the SC would make this impractical, even if I could carry the fuel. For the training market, an all-metal aircraft must look much less of a risk than the others, and the Piper name will win a lot of orders. If anybody would like to take the above, add in the Skycatcher and fill in some of the gaps, there would be an excellent basis for a magazine article.

Rod1

[IO540]

but they do seem to cruise at greater heights where they can

They must have invented a new type of stealth technology, effective in the visible spectrum, because I have never seen a ML at any "height"

A ML at 2500ft is a rarity.

FWIW

[VictorGolf]

Like the original poster, I had a look at the SportCruiser to replace my Airtourer, which is a low-wing 2-seater with a 115 Lycoming. Taking Rod's figures, the wing loading for the SportCruiser seems to be about 9.3 lbs/sq ft in old money. My Airtourer works out at 13.8 lbs/sq ft. so should give a better ride in turbulence due to the higher wing loading. However if the bumpy ride I had today en route to Turweston is anything to go by it would have been MOST uncomfortable in the SportCruiser. This bears out several comments I've heard to this effect. It will be interesting to see how they fare in the training role when EASA get off the pot and certify them.

[Rod1]

IO540

Could you tell the difference between an MCR SEP and an MCR ULM micro, or a Eurostar VLA and the micro version? I think not…

Rod1

[barne_as]

I think that a typical Cessna 150/152 has a wing loading of around 10lb/sqft so this should be something like a sportcrusier.

Most people should be familiar with the ride "quality" and comfort of a 152

[IO540]

Could you tell the difference between an MCR SEP and an MCR ULM micro, or a Eurostar VLA and the micro version? I think not…

I don't think so, but I can tell the difference between any of the above, and fresh air, and the relatively numerous (a term which I don't dispute) population of light/sport/ML planes is simply not evident higher up.

Neither are rental spamcans, but that isn't the point, given that you and Hatzflyer keep saying how the non-CofA numbers have totally overtaken the CofA scene.

Most people should be familiar with the ride "quality" and comfort of a 152

Pretty crap in any turbulence, like a fairly typical hot summer day flying under the white fluffy stuff. Even in the TB20 this is often too uncomfortable for non-GA passengers.

[Shoestring Flyer]

Any 600kg MAUW plane is not going to ride the bumps like a 2400kg plane, common sense really.
Flying in todays economic climate for most pilots is about finding a compromise you can live with. If you can still afford to fly an old Lycsaurus gas guzzler and you are happy with the way it flies then I suggest you stick with it.
If on the other hand you want to try getting more bang for your buck then you will have to make maybe a few slight compromises and putting up with the odd bump in hot weather is one of them..
For my part I built a Sportcruiser and after 15months flying it I love it and certainly wouldn't go back to flying an old stupidly expensive spamcan.
Just quoting comparison numbers though unfortunately does't even begin to tell the full story about any aircraft but if you want numbers there are currently 87 Sportcruisers/Pipersports on the UK register, not bad I think in just over two years since the first kit arrived in the UK and a hell of a lot more than other makes quoted on here.
So whilst it is not a perfect plane (is there one?) I think it is nice plane that I can put into and get out of any 300m strip, gives reasonable performance and handling and has room for lots of bulky baggage and a couple of biggish people. A plus factor as well also has to be that it is arguably the best looking small aircraft around..

[Shoestring Flyer]

....or even 1320lbsMAUW compared to 2400lbsMAUW! A slight case of the mixed weight measurements

[hatzflyer]

Io what's your problem? This guy started this thread asking for comments about lighter aircraft,especially with regard to turbulence.
you come on here yet again and try to start the old slanging match against LAA types.
You are boring.