Minnesota Father and 3 sons missing in Wyoming.

[flyingcheesehead]

Another is a well-known, highly respected DPE that plowed a SEL into the side of a mountain in the Adirondacks. IMC, at night.

Another local DPE flying a deiced A36 collided with the ground a few miles short of the Cumberland Airport. IMC, at night.

CFIT doesn't care how many engines you have.

 

[flyingcheesehead]

And a twin won't always save you. I know of an incident with a 58TC Baron. On contract with the Forest Service doing fire spotting around Leadville. Lost an engine and found he couldn't hold altitude with one. He drifted down looking for a place to land and finally go maintain 11,000 or so. Put it down on an old road in South Park. Granted it was hot. John, a multi-thousand hour pilot from Atlanta admits he got a good reminder of DA that day. He said he never thought a TC wouldn't get him back to PUB in good VMC.

The 58TC's single-engine service ceiling is only 13,490 feet - And that's a density altitude. Considering that even in the evening on an August day at Leadville the DA was 2300 feet above field elevation, I'd say that 11,000 or so is all he should have expected to maintain on one engine.

 

[ejensen]

The 58TC's single-engine service ceiling is only 13,490 feet - And that's a density altitude. Considering that even in the evening on an August day at Leadville the DA was 2300 feet above field elevation, I'd say that 11,000 or so is all he should have expected to maintain on one engine.

And he was reminded of that, big time. Lucky he was able to put it down with no damage. Flew it out a few days later.

Is that all? Even light, 2 people no luggage and partial fuel?

 

[flyingcheesehead]

And he was reminded of that, big time. Lucky he was able to put it down with no damage. Flew it out a few days later.

Is that all? Even light, 2 people no luggage and partial fuel?

That's at gross, and power loading does make a huge difference - But I wouldn't expect the 58TC to be a full-seats full-fuel kind of bird either. I know that in certain twins of that size I've had to take fuel out with only three people aboard. The turbos and their associated hardware can take up a fair amount of weight, too.

Also, the numbers are of course for a brand new airplane with a test pilot. Often as airplanes age they gain dents, antennas, dirt, etc. which add extra drag, maybe the prop doesn't feather quite all the way, etc.

13,490 does seem to be a bit low for a turbo bird, though. Maybe its critical altitude was fairly low?

 

[ejensen]

That's at gross, and power loading does make a huge difference - But I wouldn't expect the 58TC to be a full-seats full-fuel kind of bird either. I know that in certain twins of that size I've had to take fuel out with only three people aboard. The turbos and their associated hardware can take up a fair amount of weight, too.

Also, the numbers are of course for a brand new airplane with a test pilot. Often as airplanes age they gain dents, antennas, dirt, etc. which add extra drag, maybe the prop doesn't feather quite all the way, etc.

13,490 does seem to be a bit low for a turbo bird, though. Maybe its critical altitude was fairly low?

Thanks, never got a MEL or was around them much except work. I seem to remember some of the smaller twins have a SE ceiling below my airport in the summer (5000' msl).

 

[flyingcheesehead]

Thanks, never got a MEL or was around them much except work. I seem to remember some of the smaller twins have a SE ceiling below my airport in the summer (5000' msl).

Oh yes - The Seminole's single-engine service ceiling is only 3800 feet IIRC.

Most normally aspirated light twins do quite poorly on one engine - It takes a certain amount of horsepower just to keep the plane in the sky at L/d max, and that horsepower is often very close to the full output of one engine. For example, the Twin Comanche uses a 160hp engine on each side, and its MGW is 3600 lb. Now, if you lose one, you essentially have a 3600 lb C172 (most 172's have a 160hp engine also). The 172 I trained in had a MGW of only 2350 lb, so that's akin to being 50% over gross in that 172 - It's not gonna climb much!

Now, when both engines are operating, pretty much the entire output of the second engine is excess horsepower which can be used for climb, so most twins with both fans on have excellent climb rates.

Interestingly enough, the normally aspirated Twinkie's single-engine service ceiling is almost twice as high as the Seminole's, and the Seminole uses 180hp/side.

Also, the Turbo Twin Comanche's single-engine service ceiling is 17,000 feet - Being able to develop more power at higher altitudes makes a huge difference! (7100 vs. 17,000)

 

[Ted]

Most normally aspirated light twins do quite poorly on one engine - It takes a certain amount of horsepower just to keep the plane in the sky at L/d max, and that horsepower is often very close to the full output of one engine. For example, the Twin Comanche uses a 160hp engine on each side, and its MGW is 3600 lb. Now, if you lose one, you essentially have a 3600 lb C172 (most 172's have a 160hp engine also). The 172 I trained in had a MGW of only 2350 lb, so that's akin to being 50% over gross in that 172 - It's not gonna climb much!

I guess it depends on how you look at "most." The Aztec, 310, and Baron do pretty darn well on one engine provided you're east of the Rockies (Lance can comment more on his Baron which is the only one I've flown, and Bruce can comment on his Seneca). That doesn't mean it'll be easy, but you've got the power there. The trainer twins out there give you poor single engine performance, but the trainer twins aren't the ones that actually have to work for a living.

What would be more interesting to me would be things like a Navajo up through 421.

 

[jesse]

Now, if you lose one, you essentially have a 3600 lb C172 (most 172's have a 160hp engine also). The 172 I trained in had a MGW of only 2350 lb, so that's akin to being 50% over gross in that 172 - It's not gonna climb much!

Actually it's worse then that because the engine is way the hell out on your wing forcing you to generates a hell of a lot more drag then would be required if the engine could be moved to your nose.

 

[gismo]

Actually it's worse then that because the engine is way the hell out on your wing forcing you to generates a hell of a lot more drag then would be required if the engine could be moved to your nose.

When flown at the proper Vyse with appropriate bank and rudder input for zero sideslip I don't think the drag associated with the engine's location is significant. Most of that comes from the deflected rudder and the small increase in AoA required to offset the lift lost to the two or so degrees of bank. OTOH, the drag of the other (dead) engine is probably noticeable. That's the reason you're supposed to close the cowl flaps on the dead engine, it reduces the cooling drag which accounts for much of the engine's drag.

 

[jesse]

When flown at the proper Vyse with appropriate bank and rudder input for zero sideslip I don't think the drag associated with the engine's location is significant. Most of that comes from the deflected rudder and the small increase in AoA required to offset the lift lost to the two or so degrees of bank. OTOH, the drag of the other (dead) engine is probably noticeable. That's the reason you're supposed to close the cowl flaps on the dead engine, it reduces the cooling drag which accounts for much of the engine's drag.

I wasn't talking about the engine's location itself causing the drag as much as the control inputs that you must make BECAUSE of the engine's location...Combined with the extra prop and cowling hanging off the wing as you mention.

There are certainly more drag issues and general handling issues then a 3400 lb 172 with 160 hp on the nose would have. Actually I bet a 3400 lb 172 would hold a decent altitude and still fly pretty honest provided it were in CG.

 

[Ghery]

Yes -- since an engine failure IMC at night SEL is likely a fatal.

And a friend demonstrated this summer that an engine failure (well, looks like he threw a blade) VMC during the day SEL over the Rockies was fatal, too.

http://www.ntsb.gov/ntsb/GenPDF.asp?id=CEN10FA458&rpt=p

Be carefull out there.

Oh, and while studying for my IR written a few months ago I noticed that a number of the flight planning examples were in Colorado. And the MEAs were well beyond what anything I fly could reach. So, to me, IFR over the Rockies in Colorado is a non-starter. At least all I have to do here is dodge one or two rocks and stay out of icing conditions. Dodging Mt. Rainier, easy. Staying out of ice much of the year, not so much.

 

[flyingcheesehead]

I guess it depends on how you look at "most." The Aztec, 310, and Baron do pretty darn well on one engine provided you're east of the Rockies (Lance can comment more on his Baron which is the only one I've flown, and Bruce can comment on his Seneca).

Well, it also depends on how you look at "poorly" which I would loosely define as <500fpm at sea level. The 310's all supposedly do between 300-400, the C and later Aztecs are all ~250fpm (amazing what that 400-lb gross weight increase from the B to the C did, the A&B's got 365), the Senecas are around 200-250, and the Barons are all over the board but mostly between 250-400 fpm. (There's a "58 300hp" on PilotFriend that claims 626.)

So, I still call that "poor" - Most were <400 fpm at sea level, and with any increase in DA that little bit of excess horsepower is going to go away quickly in the normally aspirated models.

That doesn't mean it'll be easy, but you've got the power there. The trainer twins out there give you poor single engine performance, but the trainer twins aren't the ones that actually have to work for a living.

Looking at the "trainer" twins, though, they're not much (if at all) worse in many cases. Even a 150 Apache gets 240, better than a P-Baron! Twinkie gets 260, and even the doggiest of them all, the Seminole gets 212.

What would be more interesting to me would be things like a Navajo up through 421.

Navajo: 230-255, depending on version.
421: 300-350.

Frankly, piston twins in general don't have so much of a power:weight ratio as to really have great OEI performance. If you want single-engine performance that doesn't pretty much suck, you need turbines. Look at the Cheyenne (basically a turbine Navajo) and the I does >400 fpm, the II and III significantly better, almost 1000 fpm in one case.

 

[TangoWhiskey]

Frankly, piston twins in general don't have so much of a power:weight ratio as to really have great OEI performance.

I was curious what the DA42 TwinStar's single engine climb performance is, after reading Kent's notes above. Found this:

I've read that an engine shutdown and prop feather in the Twin Star is remarkably simple and quick, which is fortunate because the single-engine climb performance is a sobering 170 feet per minute at sea level under standard conditions. Compare that with 250 feet per minute for a Duchess at gross weight under the same conditions. The Twin Star can sustain a climb rate on one engine up to 6,000 feet...

 

[Everskyward]

Keeping in mind that all my piston twin experience was based in Colorado, I always had the mindset that the second engine would give you more options in certain circumstances but was not a panacea. There's also a big difference between losing one engine at cruise and losing one right after takeoff. I flew over the mountains, frequently, but then I also flew singles over the mountains. I would not do it in icing, though, and only limited IMC.

 

[Ted]

Looking at the book numbers really doesn't give a good picture of what the twins will actually do, though. And you're never losing an engine at sea level unless you take off right out of Long Island.

That gross weight figure especially isn't necessarily helpful, either. Sure, at gross you may have that rate, but the reality is that on the Aztec and 310 I have a hard time getting anywhere near gross weight.

So now let's look at a practical trip, like three people in each airplane. Then let's look at how well the Twinkie, Seminole, etc. does vs. the Aztec or 310. Let's also see how well the Navajo or 421 do when you try to get to an airport - the book doesn't tell you how long before your one good engine starts running high on oil temp or CHTs. That's what I care about, because to be honest the book numbers give me a vague indication, but nothing really useful.

 

[Everskyward]

Looking at the book numbers really doesn't give a good picture of what the twins will actually do, though.

No kidding. I couldn't believe the book numbers on the C-320 when I looked them up the other day when we were discussing this in chat. SE service ceiling of 18,000? No way in its wildest dreams!

 

[Ted]

No kidding. I couldn't believe the book numbers on the C-320 when I looked them up the other day when we were discussing this in chat. SE service ceiling of 18,000? No way in its wildest dreams!

Exactly. All the way around, you need to fly the plane in a realistic configuration and see what it'll do.

 

[flyingcheesehead]

Looking at the book numbers really doesn't give a good picture of what the twins will actually do, though. And you're never losing an engine at sea level unless you take off right out of Long Island.

That was kind of my point - Very few of us truly fly from sea level, so the numbers will be even worse in a normally-aspirated bird.

That gross weight figure especially isn't necessarily helpful, either. Sure, at gross you may have that rate, but the reality is that on the Aztec and 310 I have a hard time getting anywhere near gross weight.

True, true... It's just a point of easy comparison.

So now let's look at a practical trip, like three people in each airplane.

Am I one of them?

Then let's look at how well the Twinkie, Seminole, etc. does vs. the Aztec or 310.

I only have brief experience with those two, and I have no doubt they'll do better - But are ya gonna get ≥500 fpm?

What I do have some more experience with is the Seneca - And the Seneca II with three people (granted, not FAA-standard people) we had to remove 30 gallons of fuel. However, that same bird, despite being 30+ years old and having over 12,000 hours TTAF, actually got book performance in all aspects (climb with both 1 and 2 engines turning, takeoff and landing distance, cruise speed, etc). I was impressed by that, if nothing else!

 

[bbchien]

What I do have some more experience with is the Seneca - And the Seneca II with three people (granted, not FAA-standard people) we had to remove 30 gallons of fuel. However, that same bird, despite being 30+ years old and having over 12,000 hours TTAF, actually got book performance in all aspects (climb with both 1 and 2 engines turning, takeoff and landing distance, cruise speed, etc). I was impressed by that, if nothing else!

Uuuhh Kent...... even with 123 gallons reduced to 93 gallons, the HEAVIEST Seneca V ought to have 900 left for the cabin.

If three guys top that out....well, that's not very flattering to them, is it.....

 

[flyingcheesehead]

Uuuhh Kent...... even with 123 gallons reduced to 93 gallons, the HEAVIEST Seneca V ought to have 900 left for the cabin.

If three guys top that out....well, that's not very flattering to them, is it.....

This was a II, not a V. I don't have the data on that airplane handy, but I think between the three of us we probably weighed 800 lbs, plus 93 gallons of fuel at 558 lbs. Looking at the Seneca data, we probably did not load it all the way to max gross. The 228 lb difference between that and MLW would take about 1.7 hours to burn off at 22 gph so we were probably somewhat concerned with landing weight - It was a 1.2 hour training flight (including ground time), with only 1 landing (it was mostly airwork). So, we would have been at least 100 under MGW.

Like I said, though, NOT FAA-standard people... Sigh. At 6'4" if I was FAA-standard I'd be anorexic.

 

[Ted]

That was kind of my point - Very few of us truly fly from sea level, so the numbers will be even worse in a normally-aspirated bird.

Yes, but that's if you're at gross, etc.

True, true... It's just a point of easy comparison.

But not necessarily an accurate or realistic point of comparison. I would tell you that for my average trip I'd do better than book based on my load. And more importantly, if I lose an engine in-flight, I have a sufficient single-engine service ceiling to make it to another airport, which I wouldn't have in any of the trainer twins out there.

I only have brief experience with those two, and I have no doubt they'll do better - But are ya gonna get ≥500 fpm?

The other night I was getting well over 500 fpm on the 310 when I pulled the right engine down to idle after I lost a mag and the #6 CHT skyrocketed (bad plug). So it was a good simulated OEI, left engine doing all the work. But, that's a Colemill conversion on a cold night with just me in the plane (I was doing better than 1500 fpm with both at climb power). At gross on a hot day I wouldn't expect 500 fpm, but I haven't tried it. And I never fly it at gross. Meanwhile, a Seminole you will be flying at gross a LOT more, simply because you don't have much room to play with.

There are a lot of factors that go into single engine performance, and I would pay a lot less attention to the book than to someone who flew the planes and can tell you what they'll really do.

 

[flyingcheesehead]

Yes, but that's if you're at gross, etc.

I just had to go back and look at how this got started - I was trying to explain something to someone who hadn't gotten a multi rating, and the airplane in question was a turbo Baron.

Was it my suggestion that most light twins suck on one engine? I'll still stand by that - With the possible caveat that the less "light" they are, the more options the pilot has in general. Power loading is king here.

I would tell you that for my average trip I'd do better than book based on my load.

When I mentioned book values on that Seneca, the weight was included in my calculation of "book" values.

And more importantly, if I lose an engine in-flight, I have a sufficient single-engine service ceiling to make it to another airport, which I wouldn't have in any of the trainer twins out there.

I think that's a pretty strong statement to make - Even at gross, most trainer twins will stay aloft and get you to an airport if you lose one in cruise, or back to the departure airport if you lose one in the climb. The Seminole is, of course, an exception. They may not climb too well, but they're not gonna fall out of the sky either.

The other night I was getting well over 500 fpm on the 310 when I pulled the right engine down to idle after I lost a mag and the #6 CHT skyrocketed (bad plug). So it was a good simulated OEI, left engine doing all the work.

CHT went up? Or did you mean EGT? (as the thread creeps further ) What would cause CHT to go up with a bad plug? What phase of flight did it happen in? Interesting stuff.

Meanwhile, a Seminole you will be flying at gross a LOT more, simply because you don't have much room to play with.

Yup - And the Seminole is about the suckiest twin there is to start with.

 

[Ted]

I just had to go back and look at how this got started - I was trying to explain something to someone who hadn't gotten a multi rating, and the airplane in question was a turbo Baron.

Was it my suggestion that most light twins suck on one engine? I'll still stand by that - With the possible caveat that the less "light" they are, the more options the pilot has in general. Power loading is king here.

I'd encourage you to get some more multi time in various aircraft and explore the envelopes before making as many statements as you do about them. A POH is a particularly useless document when you're staring at the side of a mountain. A knowledge of the aircraft through experimenting with the real thing will be a lot more helpful. That's why I say, talk to people who've flown them.

One of my friends has a Travel Air. He had an engine fail on him right after takeoff after annual some years back (servo fell off). He was by himself, well below gross. He flew down the river for about 10 minutes before he was able to get enough altitude (not very much) just to clear the ridge to turn around and come back. When I've done training practice in the Aztec, I'm able to do a traffic pattern at Williamsport that's really not all that much of a 747 pattern.

The book discussion isn't very useful, because it doesn't take into account any of the factors that determine whether you make it to an airport safely. I'd talk to Dave S about P-Baron performance before saying that the Twinkie does better on one engine than a P-Baron (a very strong statement, especially since the P-Baron gives you the added advantage of typically being much higher in cruise).

I think that's a pretty strong statement to make - Even at gross, most trainer twins will stay aloft and get you to an airport if you lose one in cruise, or back to the departure airport if you lose one in the climb. The Seminole is, of course, an exception. They may not climb too well, but they're not gonna fall out of the sky either.

At what altitude and what airspeed? You've got a single engine service ceiling of under 4000 ft for a number of them, and that's a book value (who knows what actual is, obviously it depends). That will work fine in Wisconsin (again, a mission issue), but not near me, and I live near the baby mountains that don't really count.

Part of the reason why I like the Aztec and 310 is that, east of the Rockies, I have a good single engine service ceiling without having to maintain Vyse to stay aloft, and have good confidence of being able to make it back to the airport, even loaded in the summer.

CHT went up? Or did you mean EGT? (as the thread creeps further ) What would cause CHT to go up with a bad plug? What phase of flight did it happen in? Interesting stuff.

CHT went up, EGT went down. Classic detonation. Plug was fouled, had hot spots, and there you go. No indications other than the JPI. I reacted properly, we fixed the mag and cleaned the plug, and that cylinder has been working just fine for the subsequent 12 hours of flying.

 

[flyingcheesehead]

At what altitude and what airspeed? You've got a single engine service ceiling of under 4000 ft for a number of them, and that's a book value (who knows what actual is, obviously it depends).

The only one that I can find data for that the book single-engine service ceiling is below 4000 on is the Seminole. It's a dog, no doubt. But, I couldn't find ANY other ones below 4000. The Grumman Cougar is the only other one below 5000 that I could find - The Twinkie, Apache, TwinStar, Duchess, etc. are all higher.

I'd encourage you to get some more multi time in various aircraft and explore the envelopes

Is that an invitation? I would love to, but I only have access to a Seneca and a Duchess around here. I should go fly the Apache in the summer (it did quite well in November).

A POH is a particularly useless document when you're staring at the side of a mountain.

Agreed - I'm only using the book numbers as a point of comparison, and some numbers that we can expect we won't do better than. A Twinkie getting an actual SESC of 6000 feet at gross would be expected, a Seminole getting the same would be a miracle.

There are so many variations between individual aircraft even of the same type that it's more difficult to make comparisons between them, whereas the one airplane you're actually going to be flying is one that you want to test and know like the back of your hand. But using real-world experience of only one aircraft of a particular type compared to one aircraft of another particular type is maybe even more useless than a POH comparison when you're talking about comparing the aircraft types. Also, if you look back at the start of this discussion, we were talking about a turbo Baron that could only hold 11000 MSL on a hot summer day, and I pointed out that based on the POH numbers would indicate that you shouldn't expect to do any better since the DA was likely very close to the book SESC.

I think we're mostly in violent agreement here.

That will work fine in Wisconsin (again, a mission issue), but not near me, and I live near the baby mountains that don't really count.

They sure as hell count if you lose one before you're above the peaks! (I think the "don't count" arguments are those who are flying over them, not those who take off between them as you do - I'm sure a flight into IPT would change a few people's minds!)

CHT went up, EGT went down. Classic detonation. Plug was fouled, had hot spots, and there you go.

Ah, OK - When you said "bad plug" I thought you meant it wasn't firing at all, in which case I would expect EGT to go up due to the combustion being slower. Interesting. How much did the parameters change by? (I guess the question should be, "Just how noticeable was it?")

 

[denverpilot]

Oh, and while studying for my IR written a few months ago I noticed that a number of the flight planning examples were in Colorado. And the MEAs were well beyond what anything I fly could reach. So, to me, IFR over the Rockies in Colorado is a non-starter. At least all I have to do here is dodge one or two rocks and stay out of icing conditions. Dodging Mt. Rainier, easy. Staying out of ice much of the year, not so much.

Probably smart to remember also what the "M" in MEA stands for, as one CFI friend puts it. We pilots don't typically fly right at the edge of any range for anything, speed, engine power, what-have-you, unless there's a darn good reason and then only with all other risks mitigated.

If you're in an aircraft that's going to struggle to meet a MINIMUM your risk factors are about as high as you want them, VMC. IMC, planning flights into mountainous terrain, flying at minimum allowable altitudes, is a superb way to end up dead. You really want more margin than the minimums up there.

A bare minimum of 1500' of VMC above the MEA seems reasonable. And that happens so rarely in the Rockies, well... It just doesn't very often.

Trained airline crews with two or more pilots put one into a mountain up there about once a decade. That should say something too. Single-pilot IMC at MEA in the mountains in an aircraft with no performance to be much above MEA? Nooooo thanks. Ever.

 

[denverpilot]

The only one that I can find data for that the book single-engine service ceiling is below 4000 on is the Seminole. It's a dog, no doubt. But, I couldn't find ANY other ones below 4000. The Grumman Cougar is the only other one below 5000 that I could find - The Twinkie, Apache, TwinStar, Duchess, etc. are all higher.

With my home airport being at 5885' MSL, I've heard the joke more often than once, "The second engine in a light twin is to extend your glide to the scene of the crash." Around here, it's close to the truth.

Of course SESC is based on max-gross weight, so no one around here flies light twins with full tanks and usually not with full seats/bags/payload either.

That helps, but only gets you the ability to stay aloft and do Vmc training, with a couple people on board - that's about it. If your loaded up to max gross and lose an engine around here anytime than on a wicked cold day, you're not going to maintain an altitude above ground level.

If crashing, the lower energy of a typical single's groundspeed vs the higher speeds necessary for twin is a lot more survivable. Never searched or heard of a search for a downed light twin where anyone walked away. A few survive, but have to be airlifted out. Singles, people have about a 50/50 chance prior to exposure if the aircraft hits under control and the pilot hits the "softest" stuff that they can. (Aspen trees bend. Pine trees don't much.)

One night out without shelter and heat, that percentage drops dramatically.

 

[flyingcheesehead]

A bare minimum of 1500' of VMC above the MEA seems reasonable.

For what? That means you have VMC for 3500' above the highest terrain within 4 miles of your course. If the weather's that good, why bother with IFR?

I'm perfectly comfortable flying at the MEA (provided it's an allowable cruising altitude - The "odd" MEA's like 15,300 aren't something you're going to file) - There's a pretty good margin built in to the MEA already. Even in the Rockies, unless winds aloft are just crazy.

And that happens so rarely in the Rockies, well... It just doesn't very often.

Without a turbo, it's pretty much a moot point anyway out by you!

With my home airport being at 5885' MSL, I've heard the joke more often than once, "The second engine in a light twin is to extend your glide to the scene of the crash." Around here, it's close to the truth.

Yup - And under those conditions, you're not talking single-engine climb rate any more, you're talking drift-down. They sure glide better than singles though.

Of course SESC is based on max-gross weight, so no one around here flies light twins with full tanks and usually not with full seats/bags/payload either.

The same could be said for singles out there! Being a couple hundred undergross is a good thing. It's all about power loading.

If crashing, the lower energy of a typical single's groundspeed vs the higher speeds necessary for twin is a lot more survivable. Never searched or heard of a search for a downed light twin where anyone walked away. A few survive, but have to be airlifted out.

Hmmm. An excellent point. Now you've got me pondering Vyse vs. Vs. If you give up and slow the plane down, it'll be more survivable. If you keep it at Vyse, you may be able to avoid the crash, but if you don't...

 

[denverpilot]

I used to really like Mick's presentations on the topics covered in this book, back when he still worked for the FAA at the Denver FSDO.

http://www.crashandsurvive.com/

I don't have/own a copy of the book (yet) in my library though. I have some hand-outs from the meetings back then somewhere here, though.

The detailed discussion in those old original Wings program meetings about how force is multiplied by every single knot of additional airspeed you're carrying, was great.

Discussion about "what to hit" if you get a chance to choose, is good.

Gear up or gear down?... was always fun for some interesting Q&A topics. (Including my friend who pointed out that the photo of a 172RG upside down in a lake in the presentation was a 'gear-up' landing in front of a packed audience. (I laughed and booed as I tried to look like I wasn't sitting next to him in the audience that night. Ha.)

And the infamous videos of the same crash, over and over in the Rockies... the stall and incipient spin into tree-tops... almost always fatal. Mick showed that in most of those cases a controlled slow-flight into the tops of those trees, would have probably been survivable. But doing a corkscrew imitation between the trees straight down, you were dead virtually every time. He backed it up with physics and numbers for force generated, which was my kind of "must see TV".

"As slow as possible while maintaining directional control," seemed to fit most of the scenarios presented, the best.

Your comment about wind is very poignant. MEA with zero wind at peak height is probably fine. Most old-timers around here call "knock it off" for a mountain flight anytime the wind speed at peaks or passes is predicted or measured at 15 knots or higher in light aircraft. The rotors and down-drafts on the lee-side of any rocks can exceed 2000 FPM at 15 knots or greater. And do. Trucking along at MEA in the lee of a 14K mountain, even at 15K, you're likely to get rocked.

Without the ability to see the terrain, you can't take advantage of commonly used techniques, like moving to the downwind side of the pass and hugging the mountain after you've made that 45 degree escape turn. (Never approach a pass at 90 degrees, always approach at 45 degree angle so you have 45 degrees less to turn to escape, and that much longer wings-level (maximum lift) to get up and out of there!) Wind pushing against that mountain will rise, like rocks in a river...

But IMC, most airways go right square 90 degrees over the pass, and unless you're following along on a VFR chart, you have no idea where the areas are that you might be down-wind of a big mountain, or even when you're in the pass itself, on the Low Altitude Enroute chart. You really need to have both out (or I know... in your case, Foreflight and switch) to visualize the wind direction, where it's going to flow faster (venturi effect through passes/canyons), where it's going to get torn up by rocks poking up into the stream, etc.

Winds aloft forecasts are great... and you can visualize the flow on a VFR chart. Certain passes here are known as "airplane killers" because they're oriented Northwest to Southeast, and the prevailing winds are that direction in winter... rotors on the downwind (southeast) side are massive. Other passes are bad because they require long periods of time at high altitudes, and don't give you an "up and over quickly" option. Many people balk at Hagerman Pass (follow the power lines on the VFR sectional over the ridgeline northeast of Aspen across to Leadville) because it's really high... but if the aircraft can do it, it's way better than some of the long craggy miles-long passes down in the Sangre de Christo mountains down south, because you have a limited time at the highest altitude and plenty of steeply lower terrain on either side to escape into. "Well-defined" high passes like Hagerman are better than long high slogs over high terrain to get to a pass, and then not even really know exactly where you crossed it.

All of this stuff is REALLY hard to see/visualize, IMC. This is why every CFI who's lived here a while simply says, "Don't" when you ask about IMC in the mountains in a light aircraft. Not enough "outs".

If you're at MEA, encounter a 2000 FPM downdraft, can you make the turn back to reverse course in the terrain protection provided by the MEA? Are you going to make that turn steeper than standard-rate, IMC? Can you visualize the rocks and wind patterns to decide if going forward is okay vs. turning back? Where's the high terrain? Where's the best chance of lift? The ridgeline? The mountain? Where are they?

If you can keep that whole picture sharp in your mind's eye (perhaps with help from techno-gadgets, which may or may not be bouncing off the ceiling right about now - GRIN!), tooling around at MEA in the Rockies may be an option, but you have to act RIGHT NOW to exit the sink and go toward lowering terrain if you encounter it.

 

[bbchien]

The SE normally aspirated svc ceiling is irrelvant. 4000 to 7200, it's where the water table is. The slower glide down of a crippled twin is helpful, but usually not lifesaving (getting to pavement) as you have to get over a ridge usually to get to the runway. Landing out in the Rockies is usually unhospitable. What really counts is that if you have a twin in the Rockies, it better be a fire breathing twin loaded to SE svc ceilings of 14,000.

Many pilots, even of Seneca/340/414/421 types don't get that weight is critical. My full gross SE ceiling is 13,500 with the mods (Merlins). I have to be a shave below to make it over red table, and that is with an enroute failure. If I have a failure during climb, the question is can I turn and reintercept the inbound course.....(Eagle, and Aspen).

Going to Jackson in a week. I'll be about 200 undergross.

 

[Everskyward]

What really counts is that if you have a twin in the Rockies, it better be a fire breathing twin loaded to SE svc ceilings of 14,000.

Even though I have many hours in singles and light twins in the mountains I never did serious IMC or approaches in IMC until I was flying a King Air.

 

[Anthony]

Even though I have many hours in singles and light twins in the mountains I never did serious IMC or approaches in IMC until I was flying a King Air.

And that is VERY smart.

 

[skidoo]

snip...

Your comment about wind is very poignant. MEA with zero wind at peak height is probably fine. Most old-timers around here call "knock it off" for a mountain flight anytime the wind speed at peaks or passes is predicted or measured at 15 knots or higher in light aircraft. The rotors and down-drafts on the lee-side of any rocks can exceed 2000 FPM at 15 knots or greater. And do. Trucking along at MEA in the lee of a 14K mountain, even at 15K, you're likely to get rocked.
...snip

It seems around here below 15 Knot winds aloft is not very often. If one has a single with a SC of 20K feet, and if already flying IFR, then why not fly higher such as above 18K? If VFR, then fly at 16.5K or 17.5K. Also, why fly over a 14K peak when just about anywhere nearby would be less. In areas of a 14K peak, there should be plenty of area at 12K or less. So, by flying at least 16.5K, you can stay 4.5K above terrain. In the case of crossing the Wind river range, why not just go around if in doubt...

 

[flyingcheesehead]

If you're at MEA, encounter a 2000 FPM downdraft, can you make the turn back to reverse course in the terrain protection provided by the MEA? Are you going to make that turn steeper than standard-rate, IMC? Can you visualize the rocks and wind patterns to decide if going forward is okay vs. turning back? Where's the high terrain? Where's the best chance of lift? The ridgeline? The mountain? Where are they?

I know this was a rhetorical question, but I'm gonna answer it anyway.

*IF* I had somehow managed to get myself into this situation, the reaction would be this: Immediate canyon turn (45º bank and full flaps) - That will give me the fastest safe turn rate (and yes, I've done a gazillion steep turns on instruments). No WAY am I going to keep it to standard rate, as the 180 will take a full minute and I'm already going to be well below MEA by that point, in fact that could take me all the way down to the rocks! The canyon turn allows the 180 to be completed quickly and in a minimum radius, keeping me as close to the airway centerline as possible. When the turn is complete, suck the flaps back up and point the nose down. Yes, down. This is where I'm gonna need that 2000-foot margin - to accelerate out of the downdraft. As soon as I'm out of the downdraft, an immediate climb back to the MEA. Do not, under any circumstances, descend below MEA-2000 - if I don't get out of the downdraft by MEA-2000, it's time to prepare to crash. At that point I would probably use the excess energy I had to hold MEA-2000 for as long as possible, and when it got to that point I'd slow to 63mph (in the 182) which is both Vx (power on) and stall (power off) - That would minimize both forward and vertical speed. By that point I should also have the terrain visible on the Garmin (with 1000/100 feet) and have some sort of guidance as to which way to steer to assist in avoiding ground contact, and maybe even find some assistance with lift.

I sure hope I don't get a chance to try that technique in this lifetime, though.

 

[AdamZ]

ATC tapes are released and it paints a troubling picture of the last few minutes of the families life...
Please....... Don't fly in the mountains when the weather is poor and the winds are strong..
http://www.twincities.com/minneapolis/ci_17034969?nclick_check=1
Audio is in the boxes that say part 1.2.3.4.
Tailwinds fellow aviator.
Ben.

Wouldn't even think of it on a calm CAVU day with out a mountain instruction course first.

Those tapes are chilling. He still had the ability to break the link in the chain, but did not.

yeah I wonder why he kept plugging away. I fly with Gary or solo or another pilot I might take more calculated risk. when I have my daughter on board I am a total chicken when it comes to risk.

This is the third, I believe, essentially identical accident this year.

I wish I had a clue what he was thinking and seeing when he answered that with affirmative. He couldn't have been further from the tall rocks than 10-15 miles at that point, if he had that much forward visibility I'd think it was pretty obvious he needed more altitude than he had to clear the terrain by 2000 ft. Perhaps he figured as long as he was a little higher than the ground ahead he was OK?

My guess is that he didn't know what to say and didn't want to get in trouble so he simply said yes and crossed his fingers. It wasn't his luck day.

I dunno I thought he was only 500' below MEA on the second call so perhaps he thought he could get up to MEA then hit the lee side of the wave.


So let me ask this of mountain flyers. say you are flying toward a mountain and encounter mountain wave, it is my understanding that you fly at an angle toward the rock so if you encounter the wave you can turn around quicker a turn of say 130 degrees vs 180. but what if you are flying over the mountain from the windward side then get slammed down by the wave. Ya can't turn back to the mountain so waddaya do?

 

[Everskyward]

*IF* I had somehow managed to get myself into this situation, the reaction would be this: Immediate canyon turn (45º bank and full flaps)

My question whenever I hear anyone say that they propose to do this is whether or not they would have the necessary excess energy (airspeed or altitude) to do it successfully. Remember, the premise is that you are already up at an altitude where it's a struggle to get to the MEA.

Not only that but it seems to me that in the example of this accident they were already past the highest point so turning back wouldn't have been a great idea. Turning back should have happened a ways before that like before takeoff...

According to information provided by the Fremont County Sheriff's Office, ground searchers located the wreckage at an elevation of 11,100 feet on a scree slope about 6 miles southeast of Gannett Peak.

 

[Clark1961]

So let me ask this of mountain flyers. say you are flying toward a mountain and encounter mountain wave, it is my understanding that you fly at an angle toward the rock so if you encounter the wave you can turn around quicker a turn of say 130 degrees vs 180. but what if you are flying over the mountain from the windward side then get slammed down by the wave. Ya can't turn back to the mountain so waddaya do?

Get the mountain training...you will be taught to descend once the pass is crossed. Sometimes this is reasonable (sharp terrain transition) and sometimes it isn't (over high country or a plateau). Know before you go.

Wave itself isn't so bad since it is nice smoooooth air, the rotor that is lurking under it somewhere is bad. Clouds won't always mark the rotor. Get below the rotor which should be a ways downwind from the ridge/peak. There will also be mechanical turbulence off the peak. It's not a lot of fun but I understand it's nothing like rotor. (I've been in the one but not the other).

 

[N801BH]

Wouldn't even think of it on a calm CAVU day with out a mountain instruction course first.







I dunno I thought he was only 500' below MEA on the second call so perhaps he thought he could get up to MEA then hit the lee side of the wave.


So let me ask this of mountain flyers. say you are flying toward a mountain and encounter mountain wave, it is my understanding that you fly at an angle toward the rock so if you encounter the wave you can turn around quicker a turn of say 130 degrees vs 180. but what if you are flying over the mountain from the windward side then get slammed down by the wave. Ya can't turn back to the mountain so waddaya do?

All mountain ranges are unique in their own way. And, along any range there are good places and bad places to cross. I can take off from here in Jackson Hole and head westward. I have less then three miles to gain 7000+ feet just the clear the ridgetops, not including the "cushion" needed for a pucker free crossing. The wind can and will kill you and also save you, it all depends on how well you read the terrian and the wind direction at ridgetop level. Little visual cues like snow dust blowing off cornices, or swaying of trees will go along way to keep you alive. Air behaves like water, and as any fluid flows, it has its known paths it usually takes. A good mountain course is a nice idea but to really grasp the whole concept of flying in the mountains my suggestion is to find a river, stream, creek etc, that has a pretty good flow in it and sit down for 30 minutes or so and carefully watch how the water flows around, over and under obstructions like rocks, tree limbs or any other thing in the waters path. Some of the best race drivers have a inner sense of how air flows and they can ' see air'. They use it to their best benefit and so should any pilot flying around the mountains. Even rolling terrain in the east will exibit similar characteristics, just to a lesser degree.

As for your question of range crossing, there are several ways to address it safely. If you are headed the same direction the wind is blowing ,pick an area that is between two peaks. As the airmass passes across the ridge it will accelerate as it is funneled though the gap. There will probably be more turbulance but your groundspeed will be higher and when, not if, you encounter the downdraft on the lee side you will be futher downrange and hopefully the terrain is falling away enough to be able to give away some altitude and not have any issues.

If you are approaching a mountain range with the wind on your nose then read the terrain and pick the route that has the most rising hills that lead to the range. I call it the 'ramp effect'. You can use those smaller hills as a lift enhancer to get you to the ridgeline. When you get there the updraft is usually so strong you will need to push the nose over and ride that wave. Groundspeed will look dismal but the VSI will be headed to the peg. At least around here I limit myself to 25 mph ridgetop wind velocity. Also, if the wind is constant the risk factor is not that high, if the winds are gusting all bets are off and I personally would do a 180 and put the toy back in its hangar and wait for a better day to play.

As for the Mooney that started this thread.... The poor guy flew his plane a few hundred yards south, past the tallest mountain in Wyoming, on the windward side as he approached the range, in the soup, at close to max gross weight, probably with a little ice building up and his course took him right into the lee side of Gannett peak. The rotors that form in that area with the ridgetop winds that were blowing that day would be next to impossible to overcome in VFR conditions. Trying to keep it upright while flying on instruments and in the clouds is a task that is impossible to do, and he and the kids paid the untimate price.... It is a sad but often repeated chain of events. IMHO

Ben.
N801BH
Jackson Hole Wy

 

[skidoo]

snip... At least around here I limit myself to 25 mph ridgetop wind velocity....snip

Just curious, if you were over the DUNOIR VOR (VFR) and were flying at 16,500 ft, would you consider a direct path to U12 if the winds aloft at 12K ft were at 50 Kts from 310 degrees?

 

[N801BH]

Just curious, if you were over the DUNOIR VOR (VFR) and were flying at 16,500 ft, would you consider a direct path to U12 if the winds aloft at 12K ft were at 50 Kts from 310 degrees?

Not a snowballs chance in hell would I consider that move.
It might not terimanate in a CFIT but you would get on heck of a roller coaster ride and the groundspeed would make a grown man cry.

Just my opinion though..

I would rather be a live chicken then a DEAD duck...

Ben.

Ps... Funny you should mention those numbers because as I type this that condition exists right now.

Weather Conditions for JHS
[SIZE=-1]Current time: January 17, 2011 - 1:33 MST[/SIZE]
[SIZE=+0]Most Recent Observations at January 17, 2011 - 1:15 MST[/SIZE] [SIZE=-1]1:15[/SIZE][SIZE=-1]Max since Midnight[/SIZE][SIZE=-1]Min since Midnight[/SIZE][SIZE=-1]24 Hour Max[/SIZE][SIZE=-1]24 Hour Min[/SIZE]Temperature[SIZE=-1]26.0° F[/SIZE][SIZE=-1]26.0 at 0:00[/SIZE][SIZE=-1]26.0 at 0:00[/SIZE][SIZE=-1]26.0 at 20:45[/SIZE][SIZE=-1]19.0 at 8:15[/SIZE]Wind Speed[SIZE=-1]35 mph from WNW[/SIZE][SIZE=-1]37 at 0:45[/SIZE][SIZE=-1]22 at 0:00[/SIZE][SIZE=-1]38 at 12:45[/SIZE][SIZE=-1]21 at 23:30[/SIZE]Wind Gust[SIZE=-1]53 mph[/SIZE][SIZE=-1]63 at 0:45[/SIZE][SIZE=-1]36 at 0:00[/SIZE][SIZE=-1]63 at 0:45[/SIZE][SIZE=-1]33 at 19:45[/SIZE]
Tabular Listing: January 16, 2011 - 1:33 through January 17, 2011 - 1:33 MST Time(MST)TemperatureWindWindWindQualitySpeedGustDirectioncheck° F mph mph1:1526.03553WNWOK1:0026.03353WNWOK0:4526.03763WNWOK0:3026.03462WOK0:1526.02638WOK0:0026.02236WNWOK23:4526.02742WOK23:3026.02139WNWOK23:1526.02333WNWOK23:0026.03046WOK22:4526.02845WOK22:3026.03049WNWOK22:1526.03045WOK22:0026.02840WNWOK21:4526.03145WNWOK21:3026.02740WNWOK21:1526.02539WNWOK21:0026.02335WNWOK20:4526.02336WOK20:3025.02645WOK20:1525.02638WOK20:0025.02943WOK19:4525.02433WNWOK19:3025.02743WOK19:1525.02939WOK19:0025.02639WNWOK18:4525.02736WOK18:3025.02838WOK18:1525.03146WOK18:0025.03248WOK17:4524.03243WOK17:3024.03346WOK17:1524.03045WNWOK17:0024.03148WNWOK16:4524.03039WNWOK16:3024.02939WNWOK16:1524.02840WNWOK16:0024.03143WNWOK15:4524.03446WNWOK15:3024.03546WNWOK15:1524.03652WOK15:0024.03446WNWOK14:4524.03348WNWOK14:3024.03039WNWOK14:1524.03345WNWOK14:0024.03342WNWOK13:4524.03445WNWOK13:3024.03855WNWOK13:1524.03749WNWOK13:0024.03749WNWOK12:4524.03849WOK12:3024.03750WNWOK12:1524.03650WNWOK12:0024.03343WNWOK11:4524.03140WOK11:3024.03239WOK11:1524.03140WOK11:0024.03039WOK10:4524.02738WOK10:3023.03039WOK10:1523.03345WNWOK10:0023.03142WNWOK9:4522.03039WNWOK9:3021.03239WNWOK9:1520.03546WNWOK9:0020.03242WNWOK8:4520.03240WNWOK8:3020.02636WNWN/A8:1519.02836WNWN/A

 

[flyingcheesehead]

My question whenever I hear anyone say that they propose to do this is whether or not they would have the necessary excess energy (airspeed or altitude) to do it successfully. Remember, the premise is that you are already up at an altitude where it's a struggle to get to the MEA.

A canyon turn? Doesn't take that much, does it? I guess I was thinking that I would be starting at cruise speed, though cruise speed at 17,500 in the (normally aspirated) 182 was right around 80mph IAS IIRC, which is Vy at 10,000! But, I think I still had enough energy for the canyon turn.

Not only that but it seems to me that in the example of this accident they were already past the highest point so turning back wouldn't have been a great idea. Turning back should have happened a ways before that like before takeoff...

Right, I was responding mostly to Nate's scenario, not this accident. I was visualizing traveling westbound out of the Denver area with a headwind... Doesn't make any sense to do this with a tailwind, as you'd be turning back towards rising terrain! I wholeheartedly agree that by the time the Mooney got into the downdrafts, it was FAR too late. I'm still wondering why on earth he left the departure procedure before he was even at its MEA, much less anywhere near the OROCA.