Is a FIKI twin substantially safer than a FIKI single in the Midwest?

[Tummler]

Is a FIKI piston twin substantially safer than a FIKI piston single in the Midwest?

Assume one or two business flights per week during he winter. I don't have any intentions of launching into know ice, but it would seem like the margin of safety with a FIKI twin would be substantially greater than a FIKI single should someone inadvertently find themselves in icy conditions.

Edited the thread title to limit the question to piston airplanes.

 

[PPC1052]

Twin v. single is always a great debate. For me, I don't think a twin is safer, but I am taking into account my own abilities and training. Your mileage may vary. I suppose that the answer also depends on how heavily you will load it. If you are flying it without much weight, that gives you a greater margin of safety in the twin that might tilt the scale in favor of a twin.

 

[Tummler]

"I suppose that the answer also depends on how heavily you will load it."

Good point, and I meant to specify this. For this particular purpose, load would be substantially less than maximum gross, along the lines of never withing 500 lbs of maximum gross and usually less.

 

[RudyP]

I think it is more complicated than just that. All other things being equal, the twin is likely to give you more power, better climb rate, more redundancy, etc.. all good things. But would I take an old (early days of FIKI), non-turbocharged, very light piston twin over a brand new TBM900? No. Even limiting to piston singles, I'd rather have a newer Piper Mirage, FIKI SR22T or FIKI Cessna TTX over most legacy light piston twins for icing performance but everything has its limits.

For climbing and descending through light to moderate icing layers that aren't too thick, I like my SR22TN, the climb rate is solid (>1000FPM all the way to the flight levels) and the FIKI TKS system works very well but I wouldn't go near severe ice, SLD, or anything where I don't have a lot of outs (on top AND below preferably) in my plane. That does seem to cover things pretty well in the midwest the vast majority of the time if you are willing to plan for it though.

 

[Fearless Tower]

This is the way I look at it: a twin gives you a level of redundancy in many critical systems that is not available in most singles. But that redundancy comes at an extra cost, both in maintenance and training. You and only you can make that cost benefit decision.

 

[poadeleted20]

It can be, if the pilot builds and maintains the necessary ME proficiency. Or it won't be, if the pilot fails to do that. IOW, it all comes down to that most critical component of the aircraft -- the nut that holds the yoke.

 

[weilke]

The only thing not redundant on the SR22TN with fiki TKS is the engine.

 

[MAKG1]

What am I missing?

Most of the dangers of ice are related to the airframe, not the engines. Most twins still have only one elevator. The few dangers that are related to the engine will affect both engines in the same way.

So, how do you get extra redundancy with respect to ice in a twin?

As for power, there are some pretty weak twins as well as some pretty strong singles out there.

 

[RudyP]

The only thing not redundant on the SR22TN with fiki TKS is the engine.

This is true. The Cirrus FIKI system has dual redundant TKS pumps and tanks, dual electrical system, automatic induction air switchover, etc... but it would not be fun to be stuck in ice and have the engine fail!

Of course, there is the parachute and that does bring some comfort (at least for most of us - there are still a lot of skeptics out there) but talk about a crappy day if you had to pull the chute in icing with an engine failure!

 

[weilke]

Of course, there is the parachute and that does bring some comfort (at least for most of us - there are still a lot of skeptics out there) but talk about a crappy day if you had to pull the chute in icing with an engine failure!

The only chute that got shredded was an icing encounter.

Some piston planes had engine failures because air filters iced up and alternate air doors failed in the shut position.

For a twice/week business mission in the midwest with only the pilot on board I would get a SR22 over a twin.

 

[Fearless Tower]

The only thing not redundant on the SR22TN with fiki TKS is the engine.

It has two independent electrical generating systems?

 

[Fearless Tower]

What am I missing?



Most of the dangers of ice are related to the airframe, not the engines. Most twins still have only one elevator. The few dangers that are related to the engine will affect both engines in the same way.



So, how do you get extra redundancy with respect to ice in a twin?



As for power, there are some pretty weak twins as well as some pretty strong singles out there.

It isn't just about ice. It's the twin vs single issue in general. Ice just adds complexity to the problem.

 

[Henning]

Yes, and the reason is you have considerably more excess horsepower. Horsepower, especially excess horsepower, is you best friend in icing. Horsepower overcomes drag. Plus you end up with redundant systems to drive the deice gear.

 

[mkosmo]

It has two independent electrical generating systems?

I heard it has two alternators, so apart from the drive (engine) being a single point of failure, I'd guess yes.

 

[flyingcheesehead]

Re: Is a FIKI piston twin substantially safer than a FIKI piston single in the Midwes

Assume one or two business flights per week during he winter. I don't have any intentions of launching into know ice, but it would seem like the margin of safety with a FIKI twin would be substantially greater than a FIKI single should someone inadvertently find themselves in icy conditions.

Define "Midwest." If you're in Michigan and you're surrounded by large, cold bodies of water in three directions out of four, no way in hell would I get a single. If you're in Ohio and your business trips are to IL, that's a different situation.

If you want to go over the Great Lakes year round in a piston airplane, get a twin. Severe hypothermia sapping your ability to swim followed by drowning is not the way to go.

 

[Fearless Tower]

I heard it has two alternators, so apart from the drive (engine) being a single point of failure, I'd guess yes.

That's pretty cool. Certainly worth considering, but going back to my original statement, I would say that the SR22TN is not exactly representative of MOST piston singles.

 

[RudyP]

I heard it has two alternators, so apart from the drive (engine) being a single point of failure, I'd guess yes.

Yes, two alternators (both capable of driving everything you would need), two independent busses and two independent batteries. Pretty hard to run an SR22 out of electrons, short of an electrical fire in the cockpit that has you shutting everything down.

 

[RudyP]

The only chute that got shredded was an icing encounter.

True, but he did pull quite late (I think it was at ~300 KIAS in a vertical nose dive after getting totally iced up and the SHTF pretty badly). Note that was not a FIKI Cirrus (might have even been a clean wing plane - meaning it was one of the few SR22s without even the inadvertent TKS system but I can't recall 100%).

But I'm in agreement with you - not trying to nitpick.

 

[James331]

Depends on the plane, you can't just say a twin is always safer than a single.

I'd take a turbine single over a piston twin any day.

Trainer twins (Senecas and what not) are more like a single engine plane with a extra engine just to have a extra engine.

For ice, I'd want a turbine, boots powered by bleed air, gen going off my turbine, non electric hot lip, FIKI in a piston is more sporty than I would like, though somewhat romantic and nostalgic.

I fly a single engine IFR FIKI for work everyday, I feel very safe even at 2am in IMC with mod ice over less than agreeable terrain.

 

[weilke]

It has two independent electrical generating systems?

As mentioned, two alternators, two electrical busses. I am not certain of the details, but there is a cross-tie between the buses with some sort of diode setup. If one of the alternators dies, the other one can feed both buses but there is an annunciation on the G1000.
Of course, every fool-proof system just begs for a more sophisticated fool. You have to understand how it is all hooked together, trouble-shooting is not as simple as flipping the alternator on and off.

 

[weilke]

True, but he did pull quite late (I think it was at ~300 KIAS in a vertical nose dive after getting totally iced up and the SHTF pretty badly). Note that was not a FIKI Cirrus (might have even been a clean wing plane - meaning it was one of the few SR22s without even the inadvertent TKS system but I can't recall 100%).

But I'm in agreement with you - not trying to nitpick.

LAX05FA088

Not nitpicking either, but the plane was equipped with the 'no hazard' system. Based on analysis of the weather data after the accident, he likely encountered SLD, he could have been in a turboprop and gotten into trouble.

 

[Ted]

Depends on the equipment. In general, I prefer the extra power and generally better climb rate of the twin, but it really depends on what you're comparing. An Aztec is the best ice aircraft I've flown, period. Carries enough ice to cover Antarctica like it's nothing. A Malibu seems to be a rotten aircraft in icing - thin wing and boots are so-so. A TKS Cirrus or hot-winged Columbia would be pretty decent I'd imagine.

The 310 with 520s I fly when lightly loaded will do well over 1,000 FPM (I've gotten 2,500 FPM sustained on a light load at reasonably high IAS). It does quite well. If the icing layer is expected to be from ground into the flight levels, then you shouldn't be flying in a piston anyway. Normally it's blast up through a layer, or pick an altitude to be below or between.

More important than the plane is your understanding of weather and Skew-Ts.

What planes are you considering so we can give you better advice?

 

[steingar]

I dunno, flying business in midwest winters sounds pretty risky with just about anything short of a jet. As I understand it, most icing systems on light aircraft are designed for escape from icing conditions, not hanging out in them, which is what one is likely to do if one has to answer to a schedule in the midwest. Sounds like a smoking hole in the making. Having to meet a schedule in a light aircraft always does, at least to me.

 

[Henning]

I dunno, flying business in midwest winters sounds pretty risky with just about anything short of a jet. As I understand it, most icing systems on light aircraft are designed for escape from icing conditions, not hanging out in them, which is what one is likely to do if one has to answer to a schedule in the midwest. Sounds like a smoking hole in the making. Having to meet a schedule in a light aircraft always does, at least to me.

Pretty much why I felt a high performance naturally aspirated twin was all I really needed. I don't mind flying low, so I can get underneath most of the time, and if I can't, I really don't want to be in anything short of airliner performance.

The 310 had OEI performance down low that suited me for flying down low and making a runway.

 

[Fearless Tower]

Sounds like a smoking hole in the making. Having to meet a schedule in a light aircraft always does, at least to me.

That probably depends a lot on where you are flying/typical routes.

In the Midwest, there may be some truth to that. I don't find that to be true flying across the lower portion of the country. I'm always looking ahead and keeping options open/having outs, but I have had no problems keeping a schedule flying coast to coast in a piston twin.

 

[Henning]

That probably depends a lot on where you are flying/typical routes.

In the Midwest, there may be some truth to that. I don't find that to be true flying across the lower portion of the country. I'm always looking ahead and keeping options open/having outs, but I have had no problems keeping a schedule flying coast to coast in a piston twin.

It's really not that difficult anywhere. There are a only a few days a year in a few areas where the weather would not allow me safe flight either VFR or light IFR with a safe pop up, or through a benign solid deck. My life isn't so tightly orchestrated that I can't decide to just **** off those days and wait for tomorrow, of often a few hours, while a system moves or dissipates. I think in about 30 years the worst I got caught out by weather was 3 days, but I had found an arrangement that didn't really make me want to depart in a rush. I could have left a day earlier.

 

[weilke]

I dunno, flying business in midwest winters sounds pretty risky with just about anything short of a jet. As I understand it, most icing systems on light aircraft are designed for escape from icing conditions, not hanging out in them, which is what one is likely to do if one has to answer to a schedule in the midwest. Sounds like a smoking hole in the making. Having to meet a schedule in a light aircraft always does, at least to me.

Plenty of 210s, Ovations, Bravos and A36s fly on business in the midwest every day. It requires some judgement and skill.

 

[Ted]

I dunno, flying business in midwest winters sounds pretty risky with just about anything short of a jet. As I understand it, most icing systems on light aircraft are designed for escape from icing conditions, not hanging out in them, which is what one is likely to do if one has to answer to a schedule in the midwest. Sounds like a smoking hole in the making. Having to meet a schedule in a light aircraft always does, at least to me.

Well, I've been doing it a hell of a lot more than you almost always in a naturally aspirated twin, and never had that issue.

 

[flyingcheesehead]

I dunno, flying business in midwest winters sounds pretty risky with just about anything short of a jet.

... To a guy who doesn't even have an instrument rating.

Sorry, but I can do 99% in a high-performance normally aspirated piston single without FIKI most of the year, and probably 90% in the bad months (usually November and March).

As I understand it, most icing systems on light aircraft are designed for escape from icing conditions, not hanging out in them, which is what one is likely to do if one has to answer to a schedule in the midwest.

Icing systems on *ALL* airplanes are designed for escape, not hanging out. Look up Roselawn, that's probably the best-known example of an airliner biting it because they were "hanging out" in icing.

Plenty of 210s, Ovations, Bravos and A36s fly on business in the midwest every day. It requires some judgement and skill.

This. My own GA business trips aren't as frequent as I'd like, but I've never canceled one. The guy in the hangar across from me has been flying a booted but non-FIKI A36TN on a daily commute in the midwest for 12 years and the number of times he's had to drive is in the single digits.

 

[bobmrg]

Good point, and I meant to specify this. For this particular purpose, load would be substantially less than maximum gross, along the lines of never withing 500 lbs of maximum gross and usually less.

Richard L. Taylor once told me that he would not take off in a light twin that was loaded within 400 pounds of max gross.

Bob Gardner

 

[Henning]

Richard L. Taylor once told me that he would not take off in a light twin that was loaded within 400 pounds of max gross.

Bob Gardner

The amount of difference weight makes on OEI performance is considerable, and I agree with his findings, until you are getting into turboprop power ranges, single engine operations near gross are dicey at best. That's why I stay as light as possible. It was a rare flight that I was within 800lbs of gross at takeoff in the 310. If I can leave fuel behind on a flight in a twin, I will.

 

[AcroBoy]

I fly a FIKI twin in the Midwest, and routinely take it over Lake Michigan, Lake Ontario, Lake Erie all the time, and occasionally at night. I would not feel comfortable making the trip in a piston single, even if FIKI. Two engines means two separate and independent electrical buses, dual vacuum pumps, etc. I also have Nexrad download, stormscope, but also onboard radar. For up close, the onboard radar is much more accurate and of course real time. I postponed only one trip when there was widespread IFR, low ceilings, and icing forecast, but most of the time the extra engine and system redundancy do a lot for the comfort level of flying over the Great Lakes.

 

[Jimmy cooper]

What would buddy holly do?

 

[flyingcheesehead]

What would buddy holly do?

Irrelevant. I don't think anyone is talking about non-instrument-rated pilots here.

 

[Fearless Tower]

What would buddy holly do?

I think in retrospect BH would hire a pilot with an instrument rating.

 

[Kristin]

Re: Is a FIKI piston twin substantially safer than a FIKI piston single in the Midwes

Assume one or two business flights per week during he winter. I don't have any intentions of launching into know ice, but it would seem like the margin of safety with a FIKI twin would be substantially greater than a FIKI single should someone inadvertently find themselves in icy conditions.

Edited the thread title to limit the question to piston airplanes.

FIKI . . . SchMIKI. The question should be how fast will it climb and how well the aircraft will carry ice. FIKI is no guarantee of anything other than a reduced likelihood of the FAA trying to bust you if you land with some ice on the plane.

A lot of light twins that were certified before FIKI came out, carry ice much better than newer aircraft that have been certified. I would much rather be in a deiced Aztec, preferably turbo, than a piston FIKI single, in most cases. I understand that the TKS works pretty well, but if it fails in icing conditions, you become a meat missile in a hurry, giving you a fairly narrow window to make chute happen.

 

[AcroBoy]

I have a fiki TKS install and it works well. The cert requires dual pumps, etc. It is not a rationale for droning along in ice for hours, but does keep the flying surfaces free. It can be useful for a climb or descent through a layer on departure or arrival that increases the usability of the plane.

 

[RudyP]

Re: Is a FIKI piston twin substantially safer than a FIKI piston single in the Midwes

FIKI . . . SchMIKI. The question should be how fast will it climb and how well the aircraft will carry ice. FIKI is no guarantee of anything other than a reduced likelihood of the FAA trying to bust you if you land with some ice on the plane.

Well I think that is exactly the difference between the early days of FIKI certification and what the FAA wants to see now. The Cirrus FIKI system includes dual redundant pumps, dual fluid tanks, a dual redundant electrical system with two alternators, two busses and two batteries, multiple TKS fluid flow and pressure sensors at every critical point (tail vertical, tail horizontal, each wing, prop and windshield) with CAS annunciators, TKS gauges that read to the tenth of the gallon and calculate run time to the minute, etc...

Cirrus also had to fly 100s of hours in real and simulated conditions including a lot of flying with large foam ice shapes that simulate a failed TKS system (both full failure and partial - e.g., just one wing panel failure) to earn the certification. I've seen pictures of these ice shapes and they're like 6 inches thick. A far cry from the older, "slap some boots on and make sure they work" approach of the past.

Not saying this system is perfect or a free pass to fly around in severe icing - it requires common sense and good judgement from the pilot - after all you could always run out of fluid - but it is a pretty robust system. The FIKI certification did not come easily.

 

[steingar]

So the guys busy flaming me I only have one thing to ask. Do you have to meet a weekly schedule? What are the penalties if you fail to meet it?

Yah, lots of days in the winter you can fly just fine, I do it VFR all the time. Problem is lots of days you can't. If you're locked into a schedule, like lots of folks are in the business world, you'll wind up on one of the bad ones. Flying for business you don't always get to pick your schedule.

 

[narchee]

Re: Is a FIKI piston twin substantially safer than a FIKI piston single in the Midwes

A lot of light twins that were certified before FIKI came out, carry ice much better than newer aircraft that have been certified. I would much rather be in a deiced Aztec, preferably turbo, than a piston FIKI single, in most cases. I understand that the TKS works pretty well, but if it fails in icing conditions, you become a meat missile in a hurry, giving you a fairly narrow window to make chute happen.

My understanding is that to get the FIKI approval you have to perform rigorous testing so to claim that earlier aircraft that did not have to do this testing are somehow better seems ludicrous to me. Can you provide any references to support this statement or is this just yet another example of anybody can claim anything on the internet and there are countless fools who will believe it?