Safety (Lack of injury and death) is my prerequisite and priority

[Jethro Belle]

Every ditching can be different, but I have heard that LSA high wing aircraft tend to nose-over and invert leaving you (and much of the rear fuselage) above the water so you can tumble out onto the (briefly) floating wing and not face an underwater escape from your harness and door. I certainly hoped that would be the case when I crossed Bass Strait, (should I encounter a major problem).

I can see why you "hoped" this was the case, based on aircraft ditching videos I have seen. It supposes the aircraft hits waves level and with both wheels together so no cartwheeling initiates. It also supposes it executes just a single nice flip (a neck wrenching rotation) onto its back without the tail feathers submerging while still moving. Disoriented, you would have to exit hanging upside-down as you indicate. Just considering ditching I would want ultralight speeds to really get out without injury.

 

Perhaps manufactures need to define Vsnf for water crossings

 

I recall one story coming out of Queensland in ANO95.10 days of a ditched Scout fully submerging, as it would, being dried out and back in the air within half an hour !!! This an example of others taking risks that allow me to evaluate aircraft safety/limitations, and I was horrified back then when I heard. In defense 95.10 were flown expecting an engine out immediately so having one to start with was just a bonus. LOL.

 

Also I have been musing over turboplanner's observation:

 

The first time I ever heard of "tiger country" was when I started talking to RA people

With the helmet and racing leathers that I wore in my scout I could have flown into a tree and avoiding any large branch probably walked away unharmed. I never attempted such foolery, didn't recommend it, don't recommend it (Youth don't process risk the same. See my earlier posts), however the point is crashing into tiger country in those aircraft was not the death sentence it is in GA. Also the strips (if you could call them that) that we could use were often surrounded by trees that could not always be totally avoided, but were as much as possible. With the 500ft height restriction, engine out over Tiger Country meant you couldn't glide clear and would trash your plane and get ripped to shreds, as if attacked by a tiger. Tiger country was a risk assessment level marked on terrain surrounding strips. I suspect flying over tiger country, or at least the terminology, has carried across into the new high performance RA flying. Anyone else know the origins?

Was it your Eurofox 3k you used? That was the sort of aircraft I thought could fly Bass Straight as I wanted (a little slower than the Sonerai), but feedback here suggests good reasons it is otherwise. In such aircraft it seems to be the once off challenge mission requiring special risk mitigation, rather than a “don’t think about it too much more than normal” flight. Is that your take? How risky did it you end up thinking it was?

 

When I get a round tuit I may investigate if 'middle range' aircraft (above ultralights but still with a highish ditching risk) are the worst. Too low a capability to always avoid ditching, too fast to survive it.

 

 

[dsam]

Yes Jethro I did the trip in my Eurofox 3k (trike). Mine has all the bells and whistles (Dynon Skyview running the autopilot & showing a glide-ring on the display), ADSB, PLB, etc etc. as per my earlier post on this thread. It does an honest 110 knots TAS in the cruise, but stalls at 38 knots with full flaperons deployed (nice and slow for that rocky island I might need to aim for!)

 

Having the right equipment, doing the SKED reports, and only flying in ideal weather was my goal for good airmanship in a potentially hazardous region. Not much different to my preparations for remote outback trips I’ve done, really.

 

 

[turboplanner]

Turbo my point about bankstown is that millions of movements have happened there in the last 30 years with almost no mechanical engine failures as shown by atsb investigations. Flying safely across bass strait is more about good piloting.If I had to cross the strait regularly it would be with a lycoming or continental

OK, sorry, you made a good point about GA engine reliability.

 

 

[pmccarthy]

Having done Bass Strait behind a Lycoming and a 912ULS I can’t say that one felt safer than the other. Both low wings, done at the same speed, four crossings in each. In my circle of acquaintances I have heard of a lot more engine problems with Continentals and Lycoming than with Rotax, but nothing that would cause a mid-air crisis.

 

I must admit that this thread is causing me to re-evaluate and I don’t know whether I will do another!

 

 

[turboplanner]

Windmilling props worried me too pmc. The theory is that an UNSTALLED prop making negative thrust makes more backwards thrust than the drag from a stationary prop.Try to see this with an electric rc plane where you can adjust the rpm at will as well as stopping the prop.

I've done this and tried to see the effect but find it hard to notice. But I still believe it is there.

I just ran a comparison between a Jab J170 and an RC Boomerang trainer; The RC has a power to mass ratio 300% higher than the Jab, so it's not surprising that while the prop is turning you will still be getting some forward thrust.

In reality, if you trim for a 70 kt glide slope from altitude, you're probably not going to physically notice much. Clearly the speed won't change because you trimmed for it, but the glide slope will be fractionally steeper if there is prop drag.

 

I just ran a few angles on CAD with this result:

 

At 1000', 3% glide slope will have you touching down at 3.5 Nm out

 

4% 2.7 - a loss of 0.8 km and you are unlikely to notice this angle

 

5% 2.15 - a loss of 1.35 km, or nearly 40% short of the optimum touch down point.

 

If we use these figures based on having a top instructor in your past who programmed you to subconsciously reach for the trim lever as the engine revs started to fall, and be acting within 50/100 of a second, and then we look at a pilot who never worried much because the engine had never stopped (and several of them have posted in this thread, the time factor with "Thjs can't be happening goes out to 3 to 5 seconds and that 40% loss goes out to maybe 70%, and not looking good, and then we look at the pilot, if we can call him that, whose first reaction to the engine rpm dropping is to start diagnosing the issue, quite sure it sounds like a fuel block, so starts switching tanks etc; he's looking at a best outcome of what's pretty much below him.

 

And then you look at Performance and Operations, and if the sun has come out and it's become hot, take more percentage points off, and then on top of that, if you've packed your holiday gear and your Grossing out at 650 kg, because that's what they do in Europe, and CASA are wankers, the glideslope angle is nothing like you've experienced before, and while you might not believe this, a lot of twin jockeys overload too.

 

I know I've waffled from twins to sing single information, but it does show that glide distance is a delicate thing, and I'm amazed how often pilots post the POH glide rate on here, blindly believing they can achieve that. Personally, for my own flying, if I ever needed to calculate, I'd use POH glide distance minus 50% to allow for the above factors.

 

Also, while waffling about twins, Facthunter took a spray a few pages ago about the twins he compared to the South African Jabiru, and what was missed completely was the relevance of the engine spacing from the fuselage in an attempt to defy the moment arms of force with an engine out. Commuter jet aircraft designs also tried this in the era of the DC9 and Boeing 727 (about 50 years ago).

 

 

[turboplanner]

Having done Bass Strait behind a Lycoming and a 912ULS I can’t say that one felt safer than the other. Both low wings, done at the same speed, four crossings in each. In my circle of acquaintances I have heard of a lot more engine problems with Continentals and Lycoming than with Rotax, but nothing that would cause a mid-air crisis.I must admit that this thread is causing me to re-evaluate and I don’t know whether I will do another!

I'm sorry I misunderstood Thruster because he made a very goo point about the lack of Continental and Lycoming failures in millions of operations at Bankstown, and if you did add up the annual movements of the other GA airports around Australia, its a mission count of tens of millions.

 

While in the statistics that I previously posted on this site, which came directly from the RAA official incident reports, did show almost no Rotax failures, the three or four which showed up did include one where a plug fell out, and others where the fat fingers of the owner would have been better spent eating fish and chips.

 

For Bass Strait with the safety level Jethro was looking for, you have to be looking at the very best results from an aircraft group, and, while you almost certainly could find someone to put your Rotax into the professionally maintained group, you just can't get the avionics required for this target into anything less than a GA size instrument panel and weight limit.

 

That's not to say people can't get across on a Drifter, because, they can, but the risk is exponentially higher, and there are plenty of "Dr Livingstone, I presume" posts on this site the adventurers can read.

 

I can understand your first line; if you aren't worried about it you don't feel any apprehension, and after all you can see the coast or the edge of the forest out there the horizon, and then I started reading "The Killing Zone and realised I had become an idiot, and realised it was so easy to extend my life.

 

Regarding your last thought, at times its $39.00 on Jetstar. I stopped doing steep turns, and just flight planned away from potential hazards.

 

 

[facthunter]

Regarding props windmilling or stationary, a wind milling prop if it spun freely would not cause much drag until the RPM's got right up and the tips went supersonic. If the prop is spinning and it is driving something that absorbs a lot of power (like a failed turbine) It has the ability to absorb multiples of the normal thrust figure because of the gearing and the torque of fast turning the dead engine and compressor as well as the ancillaries driven from the engine. For this reason turbo props pretty much universally have auto feather which acts almost instantly if the torque on the drive reduces. There is a sensor that triggers the autofeather. but it's not active at low power settings.

 

A stopped unfeathered prop will have drag depending on blade area and acts on a V squared rule so varies with the speed through the air. There is a concept called flat plate equivalent used on form drag calculations in aircraft design performance predictions. I don't know what the drag would be but holding it out of a car window at 50 K + would be a considerable effect but potentially much less than when the prop is aerodynamic A rotating prop has much more ability to absorb power and create drag (or thrust) as it's in an aerodynamic situation and is efficient (not stalled).

 

If you are on an approach with engine idling at say 850 rpm and the prop ( fixed) pitch is 36 inches , at normal approach speeds the airflow will be driving the engine and consequently slowing the plane a bit as the air through the prop with out slippage is 850 x 3 = 2550 fpm which is only 30 mph far less than your approach speed. If you divide your approach speed by the "actual" pitch of the prop you obtain the RPM figure at which the engine would be neither propelling it or slowing it down. Keep all your units the same and you should know your airspeed errors and use a True Airspeed. Its quite a high rpm figure before it starts providing actual positive thrust.. Calculate your own planes figures and see.. Nev

 

 

[Bruce Tuncks]

Good stuff Turbs. I can verify your point about how you need to investigate the actual glide angle by experiment instead of just looking at the POH figure.

 

In my Libelle ( POH best glide 38:1, test result 35:1) the actual real-life glide figure is more like 24 to 1.

 

Why? well in real life you will have a few bugs on the wings and you will be flying through sinking air more than through rising air. Also any turbulence will drop the figure.

 

On a final glide coming home to Gawler ( into a sea breeze for the last 15k ) I like to have about 20 to 1 in order to have some energy and options on arriving at the field. This is about HALF the POH figure .

 

In the Jabiru, I reckon 12 to 1 is about right. This is at 60 knots but most people fly a lot faster when they are simulating an engine out.

 

 

[facthunter]

If gliding into a head wind a faster airspeed is required for max range.. You are being blown away for less time. Ground speed over sink rate will be best figure you aim for. Consider you are gliding at 60 knots into a 60 knot wind You will never get there. Less than 60 airspeed and you are going away from your destination. At 90 knots you are closing at 30 knots ... Nev

 

 

[pmccarthy]

In the book by Jaros, Engine Out Survival Tactics, he suggests holding your arm out with four fingers extended, place the top of your hand on the horizon, and look under the bottom finger to see where you might glide to. Simple and rough, but it might give a good wake up call to optimists.

 

 

[facthunter]

Some thing is better than just guessing, but it's not very precise or scientific.. You should be aware of the wind direction and speed in your planning and revised estimates and being high is OK . Being low is the "don't get there" category. If the only suitable place is some distance away you have a problem. You might be better off picking something closer.. In remote areas I would see getting a long way from roads as a bad idea in a single so why should the maximum range be so critical in a general sense.? You Do know your power off sink rate though the prop will be stopped this time. Generally that's NOT a big variant. If you are at 3.000 ft above terrain you have about 5 minutes 4 to be on the safe side especially if you are turning much.

 

How many can actually judge distance very accurately?. Also without the usual earth features like suburbs to provide a texture that gives a concept of distance. You are not in the same familiarity league over sand dunes salt lakes or water...

 

Tighten seat belts firmly., have your PLB set up and communicate if possible but don't cock up the pilotage. Injury is serious if you don't have someone around for prompt aid.. Land into wind. less energy to dissipate. Use a track if you can see one. It at least proves a vehicle has been able to travel on it, and remember which direction the nearest road was.. Nev .

 

 

[Thruster88]

In the book by Jaros, Engine Out Survival Tactics, he suggests holding your arm out with four fingers extended, place the top of your hand on the horizon, and look under the bottom finger to see where you might glide to. Simple and rough, but it might give a good wake up call to optimists.

The POH for my musketeer says it will glide 1.7nm per 1000. The fingers are spot on, thanks for the tip

 

 

[Mike Borgelt]

If you want a safe 4 seater that isn't too expensive to run you could do a lot worse than a BD-4C powered by a Lycoming or Superior O-360. There's a great support group on line and the BD-4 has an excellent crash worthiness and low accident rate record. Front seats are inside a very strong crash cage. Systems and hardware are mostly standard parts similar to Cessna, Piper etc.

 

My wife and I have a BD-4B with O-320. Excellent aircraft, cruises in the 130 to 140KTAS range, 8 hours fuel. Likes to fly high, far and fast especially in the 7500 to 9500 foot range.

 

 

[Bruce Tuncks]

golly pmc, I got a short arm and fat fingers...well my fingers go 8cm at 52 cm from my eye. Makes 7 to 1

 

Not a bad trick, the Jabiru will do that and leave a bit safety. I'll try it next time I fly.

 

 

[BRL]

Perhaps a call to Mike Smith re whats good to fly over water and take a look at his around the world flight video

 

powered by Rotax.

 

 

[facthunter]

A few have done that sort of thing with an RV and a superior/ Lycoming. (The RED ones). One of those engines bedded in well would be my choice. They are clunkers but well sorted and simple . Just what's needed if you only have ONE over a wide ocean or the South Pole. Also CS prop compatible (certified)..Nev

 

 

[Jethro Belle]

Good stuff Turbs. I can verify your point about how you need to investigate the actual glide angle by experiment instead of just looking at the POH figure.In my Libelle ( POH best glide 38:1, test result 35:1) the actual real-life glide figure is more like 24 to 1.

Why? well in real life you will have a few bugs on the wings and you will be flying through sinking air more than through rising air. Also any turbulence will drop the figure.

The FAA agree about the risk and need for pilots determining it themselves https://www.faa.gov/news/safety_briefing/2016/media/SE_Topic_16-01.pdf

 

Also where to aim on the landing space... then more flaps or slipping to drop in earlier. No doubt you all know this.

 

 

[turboplanner]

The FAA agree about the risk and need for pilots determining it themselves https://www.faa.gov/news/safety_briefing/2016/media/SE_Topic_16-01.pdfAlso where to aim on the landing space... then more flaps or slipping to drop in earlier. No doubt you all know this.

There is the theory and there is the practical when the engine stops. More than one have kept on pulling the stick back until they simply stalled in from over 1000'; it should all come together during training.

 

 

[turboplanner]

The other class of aircraft I didn't mention because of cost is the single engine turbine, like the Cessna Caravan. Cost for these is in the $1.25 to $1.7 milion mark, but for someone wantin to range from Tasmania to Queensland, hiring is a possible alternative.

 

 

[Jethro Belle]

BD-4B

Thanks Mike,

I have spend an odd hour looking at the BD5 with a combination of admiration and fear. It amazed me the same designer produced pretty standard boxy looking high wing aircraft! I guess I passed them by as they appeared to me home built versions of commercial aircraft and to me home-building is about doing something you can't get. They are well priced (I checked) and have better performance that I would expect from the fuselage. Is that because it has a 160 hp motor hanging off the front?

 

You have convinced me to add one to my consideration given their safety record. Given many have been built for so long safety statistics are meaningful. Although unique special builds excite me, the first few 'test pilot' flights have extreme crash statics and you are the test dummy for every failure there-after. Many aircraft of type shares that risk around.

 

 

source: The famous BD-4 Kit Plane | Bedecorp

 

The fuselage looks solid around the pilot (with a big pipe to hit your head on ). I will check it in detail, if I decide to go that way and one is available.

 

 

[Jethro Belle]

The other class of aircraft I didn't mention because of cost is the single engine turbine, like the Cessna Caravan. Cost for these is in the $1.25 to $1.7 milion mark, but for someone wantin to range from Tasmania to Queensland, hiring is a possible alternative.

I could do a mobile home conversion on it

 

While the Lycoming and Continental motors are so simple (relatively unstressed, low reving ...) they can hardly fail, general agreement posted seems to be that a turbo-prop is the gold standard single engine aircraft for a Bass Straight crossing, suggesting most still have engine failure in the back of their minds. I have looked at APUs used in homebuilts, but don't think they are a safety match for a Pratt & Whitney Canada PT6A

 

 

[Jethro Belle]

Perhaps a call to Mike Smith re whats good to fly over water and take a look at his around the world flight video powered by Rotax.

I couldn't find his number anywhere. Maybe he will post himself as he has a lot of insight to offer us. Does anyone know him?

His trip blog has gone down so it is hard to assess how risky the trip was. Like around the worlds yachts people who are greeted as heros, if they are the lucky ones who survive. With his 21 hours full fuel load on board it must have been marginal flying. He is clearly a very competent pilot and did enough risk mitigation and flight logistics support, but is sounds like he was lucky from his own comments.

 

Michael Smith was approaching the broken western coast of Canada when he figured his long and solitary adventure — and probably his life - was ending. Thick fog lay beneath his little plane, Southern Sun, and heavy cloud sat above. The two systems were closing fast. Suddenly, he lost visibility. He didn't know which way was up or which was down. His plane spun out of control and reached such velocity his speedo rocketed into the red, way over its maximum reading of 120 knots (222km an hour). His perspex windscreen began caving in. "I thought it was all over," Smith remembers. .... ....

 

"I wouldn't do it again," Smith says.

 

source: Flying solo around the world in sea plane lands Melbourne pilot Adventurer of the Year

 

Sounds similar to a flight across Bass Straight into bad weather!

 

It would be very interesting to find out his assessment of the Sea-ray ditch worthiness and advantages it provided, apart from landing on calm water. It certainly provides another data point in what can physically be done (When 100 more have done it we will know the actual statistical probability). I suspect he was so busy just getting everything together logistically he didn't have much time for risk assessments other than what good pilots all know. Now he has experienced all the risks I suspect he would not advise others to copy the flight.

 

It reminds me about Revisiting the 1988 ultralight flight from England to Australia. This CFM Shadow ultralight flight distorted my understanding of what to expect from aircraft, and this thread has helped me correct misconceptions. To me these 'adventures' are increasingly cases off "Why do it - All been done before (including deaths trying)- lucky to walk away from".

 

If I have to eat my words, I will be happier than anyone because the Searey is a plane I considered. I did look at a nice Osprey years ago in Bairnsdale and when I mentioned Bass Straight the seller was not keen. When I mentioned flights to Tasmanian highland trout lakes he suggested performance limited getting off lakes at altitude. I am not comparing these modern amphibians to older home-builts, just that there are limitations with them.

 

Off course others are addicted to adrenaline and view death more lightly than I do, which is their right. Many doctors climb and some die proving themselves on Everest!

 

 

[turboplanner]

You picked it; worth studying, but, like the guy who flew an Ultralight, a lucky exception rather tan a mundane trip repeated daily for years in all weather without an accident, which is the target you set.

 

 

[Jethro Belle]

You picked it; worth studying, but, like the guy who flew an Ultralight, a lucky exception rather tan a mundane trip repeated daily for years in all weather without an accident, which is the target you set.

I did not realize how close until I read this:

"As a Visual Flight Rules (VFR) pilot, I wasn't meant to fly through cloud." ... "A minute later the Sun broke free of the cloud. The ground was only a few hundred feet below. At the speed I was descending, that would have been roughly 10 more seconds."

 

Source:Seaplane pilot Michael Smith: the moment an Aussie driving habit nearly killed me

 

Perhaps a call to Mike Smith re whats good to fly over water and take a look at his around the world flight video powered by Rotax.

I have his contact details, but he is VFR and bought his plane, so I may not bother him. He gives keynote speeches about his flight and has written a book about it in addition to the video, so he must be pretty busy doing that while running his theatres!

 

 

[Jethro Belle]

I have read about standard twins killing most typical GA pilots within a few minutes of engine failure due to their asymmetric thrust causing it to roll and power spin as I recall. It is really nasty to correct and single engine performance is marginal, so the risk reduction offered by a traditional twin barely outweighs their benefit for GA aircraft, and you pay double the engine bills.

Based on my research I must moderate/correct my earlier statement. The above applied to early post WW2 twins and pilots/pilot training at that time. After reading up, my conclusion is that: current well designed twins with competent well trained pilots will be safer on equivalent risk missions, and much safer for night-IFR, mountain and water crossings. Their high risk statistics are heavily biased by the higher risk missions they attempt, that average statistics fail to factor (the same applies to the C182 and more high performance aircraft).

 

Since Richard Collins is widely recognized as the origin of the belief that I posted, I include links to his 'perception corrections':

 

50 years ago in Air Facts and What’s wrong with piston twin pilots?

 

This thread Can we put to bed the single vs twin argument now? provides some risk statistics. It seems my original post was an old pilots' tale.

 

Twins are back on my list of Bass Straight Crossing contenders, if I can afford one. My apologies to twin owners for their good judgement.

 

footnote: From my reading the main safety risk counting against all higher performance aircraft, excluding tackling higher risk missions, is the higher kinetic energy that you possess when you crash (Fights home on one engine do not appear in standard statistics), making the outcomes more severe. I hope I've got it right this time