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WLM
30th Nov 2003, 12:58
A question I have been asking myself lately, which someone may have an answer for.
I am now flying an R44 instead of Bell aircrafts and find the lapbelt, car lookalike, a little "unerving". That might be a personal state of mind I suppose. Do others feel the same? Is there a conversion legally approved for standard lapbelt to harness available? Or is this lapbelt as good as a harness when the crunch is up?
Tks. WLM :O

ShyTorque
30th Nov 2003, 16:19
A lap belt is only a "lower body restraint" to keep you in the seat, so the upper body is presumably not restrained at all.

In the event of a forwards or sideways impact, use your imagination about what could happen, especially if a protective helmet isn't worn.

A personal choice. Not for me, thanks. :uhoh:

Helinut
30th Nov 2003, 17:16
WLM,

Unless they have changed recently R44s are fitted with lap and diagonal chest restraint belts. However, your point is well made that the degree of restraint is less than a full harness.

The R44 belt only has 3 hard points on the airframe per seat. This rather limits the options. I cannot imagine that Frank would be happy for you to go drilling holes in his design:)

I am a bit worried by the reliability of the inertia reel found in many restraints, but having them certainly makes it easier to stretch to far flung parts of the cabin.

Mars
30th Nov 2003, 22:09
The Robinson has a modification for a four point harness - check with the dealer/factory.

WLM
30th Nov 2003, 23:04
Oops, sorry. Yes I meant the lap and diagonal restraint seat belt system in the R44.
I will check with the local dealer about the 4 points restraint harness kit mentioned.
As a matter of personal interest, why did F. Robinson choose to use the lap/diagonal system?
Cheers
WLM:confused:

Thomas coupling
30th Nov 2003, 23:08
The latest EC135 crash in Strathclyde reported that the passengers in the back would have been much less likely to have suffered their injuries if atleast a four point harness had been fitted rather than the standard diagonal (car) seat restraint.

We have gone further and fitted the anti submarine seat restraint (5 point). For what it's worth.

A simple lap strap, in my humble opinion, is a complete waste of time. Think of all that flailing around and glancing blows to the a/c structure etc :{ Then you add to this, people flying in one of these mickey mouse harnesses with little or no head gear on:hmm:

No thank you!

Any helos out there yet with air bags as standard?

RDRickster
1st Dec 2003, 00:13
Check out the following...

http://www.schroth.com/produkte/aviation/index.htm

Click on "Restraints" on the left. I don't know if they have any "approved" kits for the R44, but I'm sure they can tell you. I know that they also make "water activated" unlocking mechanisms for restraints. If you have to ditch and do not manually unlock your harness within three seconds or so, it will unlock your harness for you... pretty cool.

Steve76
1st Dec 2003, 01:44
Probably used because there is no cyclic to headbutt and if you hit your helmet into the airframe it will give before your helmet will........:hmm:
I think the lap/diagonals are inertia activated and I have seen them adequately restrain a R22 pilot who rolled along the ground at 70kts, so I guess they work.

misterbonkers
1st Dec 2003, 17:42
If they didnt work they wouldnt be fitted. Robinson helicopters were designed for civilian use, the seat belt mechanism is therefore a lot simpler to understand and passengers can fit and remove the belt easily without having to think about it too much.

WLM
1st Dec 2003, 21:24
misterbonkers

I can't see the relationship between Civilian use and Military use:confused: when you crash, I don't really think it hurts in different way....
From the various posted anwers above, we as pilots on a commercial level, generally prefer the safety and feel of a full harness. "Civilian" passengers as you mention, would probably feel the same if they were fully made aware of the subtle difference.
I am just curious on why the use of the lap/diagonal seatbelt is only used in Robinson helicopters?:suspect:

Whirlygig
1st Dec 2003, 22:27
OK, the lap belt & diagonal restraint may be simpler to use and operate for passengers but a four/five point harness is hardly a difficult concept.

A pilot should always make sure that his passengers are correctly strapped in and, if they can remember old car seat belts of the 70s, they should grasp how to use them; although the mechanism on Squirrels is v. fiddly IMHO ;) . I know which I prefer.

Cheers

Whirlygig

Helinut
1st Dec 2003, 22:29
WLM,

Lap belts and lap & diagonal belts are used in other helicopters. Most pure passenger seats have them. In general, most crew seats have harnesses of one sort or another. Perhaps the justification for no harness with the Robbos is the lack of a stick in front of the pilot that he can hit his/her head on?

I could guess that the RHC priorities might also be affected by weight and cost too - these are elements in any manufacturer's choices .......

Misterbonkers,

I would not personally have such blind faith in those involved to automatically assume that "it must be safe" - this is not a poke at RHC particularly. I just think it is naive to assume that you can be certain that people always do their jobs properly -

that's why I always do a check before flying after maintenance has been done, even when the "engineers" have signed off a daily check.

RDRickster
1st Dec 2003, 23:04
I'm not very confident in the crash worthiness of the Robbie anyway. If you've ever seen post-crash pictures, the site isn't pretty. There are exceptions where the crash is hard auto to paved runway... the skids split and absorb a LOT of impact quite nicely. Dyanmic roll overs and autos into trees with any forward airspeed are pretty brutal in the Robbie.

The B47 uses lap belt with NO shoulder restraint! The B2B and 280FX uses 4-point harness systems. I feel a little safer in the 4-point harnesses vs. lap & shoulder belt alone. Looking back at my statement above, I have to ask why I'm flying the R22 without a helmet?

That's another topic for discussion, but most of my flying is "casual" (if there is such a thing). I guess the comfort and sound quality of my Bose Aviation-X is something that makes it much more enjoyable... and it's not like I'm doing line patrol or other hazardous work in the Robbie.

Jcooper
1st Dec 2003, 23:51
I don't know about you but my damn head wouldn't fit in there with a helmet. Penalties you pay for being 6'5".

misterbonkers
2nd Dec 2003, 00:05
Ok, let me try and explain what I was saying for those of you who blatently misunderstodd where I was coming from:

One, forget commercial flying, im talking civilian as a whole. For none commercial flights, we all know that the PPL(H) often allows his passengers to sit themselves in and fasten theyre own seatbelt, especially when people are getting in and out when rotors are running. The 'one click fastens in' approach of the robinsons (for example) is therefore more likely to ensure the seatbelt is fastened properly as opposed to the four point harness which is not often (to the amateur) an easy thing to fathom out and, once fastend, should be properly adjusted into position (lap straps first, then shoulder straps.

If the seatbelt isnt fastened properly it wont work as it should - surely you agree?

So we see the diagonal system e.g. R44 is easier to understand to the person not used to air travel.

So, now were wearing any kind of seatbelt fitted properley, were more likely to survive a crash.

The UK CAA are extremely safety conscious, perhaps too much, but nevertheless, they would never approce a restraint system that doesnt meet the crash requirements. Crikey, my new R44 had to have its fire extinguisher holder relooked at because the extinguisher would come out with 13.5G impact, and the rules say 14G. For the record, before any of you think im just a robo pilot, im rated on R22, R44, Bell206, Bell47.

so as for the harnesses, Im used to both types, and I do agree that the 4 point 'feels' safer.

Secondly, in the event of an accident, panic and confusion will occur to the passengers and pilot. The pilot is used to getting out of harnesses, seatblets etc so if rapid evacuation of incident survivees is required (e.g. ditched in water, a/c fire etc) then surely (as we all travel in cars etc that have the diagonal restraint) the passenger is quite adapt at reaching to theyre hip and undoing a seatblet?


To be fair, I think the main point is the fitting/wearing of a seatblet in the first place.

No doubt plenty of you will beg to differ (especially all you experienced commercial guys) but try and think of that person who has hardly ever flown, has to get in a helicopter, and put on a seatbelt.

Whirlygig
2nd Dec 2003, 01:07
Misterbonkers - I, too, was coming from a private flying perspective. Every time I take a passenger I check their harness and also demonstrate how to undo it in an emergency. I also show them how to operate the door.

Whether private or commercial, it is still the pilot's responsibility to look after their passengers - hence the safety brief. You might think this a little sanctimonious but I take it quite seriously as my passengers tend to be family and close friends !!

I fly a Schweizer which has a four point harness. It is not much different to an old fashioned car seat belt (only with more bits). It has a flip up release so can be undone very quickly in an emergency. Harnesses shouldn't be any more difficult for passengers to deal with given proper pilot supervision and therefore I would suggest that the reason lap belts are fitted is weight and cost alone - with emphasis on cost ;)

Cheers

Whirlygig

Thomas coupling
2nd Dec 2003, 01:36
hear hear Whirlygig. Harnesses are used everywhere nowadays:
Fast road cars / bungee jumping / rallying /.
Why they aren't considered 'essential' for flying, confuses me :confused:
If you can afford your own chopper, why not $500/restraint???

Misterbonkers, give your passengers some credibility and while you're at it, some decent restraints too:ok:

RDrickster: I can't believe you really do fly around in a lap strap and no helmet...obviously one of the "won't happen to me" brigade.

Pumpkin, mush and puncture wounds come to mind.:uhoh:

RDRickster
2nd Dec 2003, 02:33
TC,

What can I say, except guilty as charged! I wouldn't ride a motorcycle without a helmet, but I will fly an R22 without one. However, you are statistically more likely to be in an accident in a motorcycle or car than you are flying a helicopter.

Still, I certainly believe that "it could happen to me." That's one of the reasons I'm a little more detail oriented than others I've seen in the cockpit. In the grand scheme of implementing proper control measures for the associated risk, wearing a helmet in such a small aircraft may actually create a hazard and outweigh the benefits.

That sounds good, but it isn't the real reason I don't wear a helmet when flying small helicopters. I've also flown the R22 Mariner, B2B, 280FX, and B47. During transition training from type to type, I've never witnessed a CFI wear one either. I don't think it's cockiness... it's a matter of personal preference and comfort.

I'm sure the topic of helmets in small helicopters was discussed on PPRuNe before I became a member... I'll do a search. I've met a couple R22 pilots at the RHC Safety Course that always wear helmets. In each case, they flew to remote locations and perform line patrol at low altitudes... so, it made sense for them.

PPRUNE FAN#1
2nd Dec 2003, 05:10
You people are funny...arguing over why the Robbie's have such wimpy restraints. So silly!

I *GUARANTEE* you that it worked out this way when Frankie R. was designing the R-22:

1. What type of restraint meets the letter of the law with respect to certification?

2. What type of restraint is the cheapest?

3. What type of restraint is the lightest?

To even fantasize that Frank was concerned with making a "safe" helicopter when he designed the R-22 is just ludicrous. All he was trying to do was make it as "safe" as possible GIVEN THE CONSTRAINTS OF THE DESIGN PARAMETERS.

Sure, we wish he would've given the cabin more structural integrity...or a beefier landing gear. Sure, we wish he had put in a four- or five-point harness. Maybe we should wish he'd stuck a three-blade rotor system on it! But he did not do any of those things. Why? Weight and cost, baby! Not due to a conscious neglect for ultimate safety, but the whole thing ended up being a bunch of design compromises.

As for seat belts, I've seen plenty of Bell 206 accidents where the belt assemblies pulled right out of their mounts - and the pilot lived! He was ejected, but he lived. In one case, the pilot was ejected through the windscreen and broke his shoulder on the centerpost on the way out, kind of adding insult to injury...or extra injury to injury. Made me realize that the strongest, most robust harness in the world is only as strong as the airframe it's mounted to. And in the case of the Robbie...

Given the choice, I would always prefer a full, complete five-point harness. But we are not always given that choice, are we? But as long as the particular restraints that are installed in the aircraft are properly secured and adjusted, any discussion about which type would be "better" with regard to a helicopter crash is pretty moot.

Finally, consider this: People panic. People revert to what they're used to. If you take a non-aviator and stick him/her in an aircraft with a restraint system that is unfamiliar, they absolutely will not know how to undo it if there's a crash. Heck, people can't do it even when there's *not* a crash.

I've had passengers who were distracted and eager to get out right upon landing for one reason or other (after flying with me, can you blame them?). First, they forget the belt and try to hop out. Then, when they realize that they're still "trapped," they search around frantically for the release mechanism. These are people, by the way, who've *all* flown before and have had the FAA part-135 briefings many, many times - including before that very flight. Yet they still forget. Usually I'll just sit there and watch them struggle. Finally, I'll say something smart-alecky like, "Gee, good thing we're not underwater...OR ON FIRE!"

So reassure yourself that you've thoroughly briefed and instructed your non-pilot passengers, if you like. But people forget. And in a highly stressful situation (like a crash) you simply cannot expect them to remember the particular seat-belt removal technique. ...Which is why it is probably better to have automotive-type seatbelts in aircraft.

Thomas coupling
2nd Dec 2003, 09:47
Poop fart 31: never been to a fun fare, never buckled into a"harness"...never lived thats your problem.

Fact is they (pax) would panic whatever you give them to wear, they just don't think.
So may as well give them a fighting chance.

Ever heard of duty of care.....

No wonder nooneflies with you :=

PPRUNE FAN#1
2nd Dec 2003, 13:05
TC:Poop fart 31: never been to a fun fare, never buckled into a"harness"...never lived thats your problem.Thomas, please repeat that again in a language that is understandable. Your "thoughts" (and I use that term very, VERY loosely) are usually incomprehensible. This time even more so.Fact is they (pax) would panic whatever you give them to wear, they just don't think.
So may as well give them a fighting chance.

Ever heard of duty of care.....Duty of care. Yes. My passengers wear the restraints provided in the helicopters furnished by my employer. If that somehow makes me negligent in my "duty of care" to my passengers, I fail to see it. If on the other hand you are proposing that my employer replace all of the seatbelts in all of our various ships with five-point harnesses, and private owners of R-22's replace their factory-stock restraints with five-point harnesses and furnish helmets to their passengers because that is the minimum "duty of care," I might suggest that you lay off the crack pipe. (Judging from your other various posts, I might suggest that anyway.)No wonder nooneflies with youOh, how wonderfully witty! You're a regular Oscar Wilde, aren't you? Probably in more ways than one.

misterbonkers
3rd Dec 2003, 21:31
TC - ive flown enough people so far in my career to know how they respond to their first flight in helicopters. Naturally, on AOC work, it is mandatory to give breifings on doors, seatbelts, locations of first aid kit, fire extinguisher, evacuation procedures, but no matter how long you spend with them, how convincing they seem when they 'understand' and can actually open the doors, remove seatbelts etc, many have forgotten when it comes to the end of the flight, when their adrenaline (sp?), is rushing, so please dont try and convince me otherwise - its easy for all of us regalur users to assume, but now and again, just take a step back and look from a wider perspective.

A common device full stop in all transport modes would obviously be a good solution, but this is the real world after all, and we know that aircraft design is about comprimise.

As for Rally Cars, fast sports cars, bungee jumping, I dont see everyone participating in these all day every day in numbers on a par with the normal everyday car.

If a device is easy to use and understand, its more likely to be used and used correctly with or without supervision. A four point harness still has to be adjusted to fit properly.

I agree with four point harnesses been safer when worn correctly, but what about the wider picture for the helicopter and 'Jo Public' .

Head Turner
4th Dec 2003, 19:06
I fully agree with 'misterbonkers'. Realism must pay an important role in everything and passengers are sure to be in a panic and confused and making a seat belt 'common' is a good way to go.
If all the keypads on mobile phones, desk phones, computers and calculators were all to the same desige layout how much easier it would be. And in this instance we have plenty of time to work out the differences - not millisecond as would be in an emergency.
May I add that some B47's do have 4 point restraints.

Thomas coupling
4th Dec 2003, 19:33
Misterbonkers and head turner:

Maybe something is lost when relaying conversations on this forum, I don't know.
But the simple point I want to get across is this:

When 'passengers' are strapped in, I admit anything other than a lap strap might be beyond them. BUT, time is in your favour, no one is panicking, so the job can get done properly.

However, should/could anything go wrong, and a crash ensue, then the important thing to remember is that no matter how 'sophisticated' the 4 point (accept 5 point over the top), 'harness' is/was to fit when they climbed in, it is
RIDICULOUSLY SIMPLE TO REMOVE. You simply twist (some models) or flick a lever to escape. NOT DIFFICULT AND AS EASY AS ANY LAP STRAP MECHANISM.

In the interim, these 'passengers' enjoy the added safety benefits associated with proper harnesses compared to car lap straps borrowed from a renault or GM:uhoh:

WLM
4th Dec 2003, 22:55
Well said TC:ok:

ShyTorque
5th Dec 2003, 03:00
One thing to remember is that undoing a harness is impossible if you are disabled due to a severe head injury


Prune Fan#1,

You are right about folk forgetting the safety brief by the end of the flight but I can't imagine YOU making a smart-alecky comment, surely that's not something you're prone to, is it? (p.s. got my harness done up, helmet on - and a book down my trousers as a backup!) :E

PPRUNE FAN#1
5th Dec 2003, 06:02
Shy Torquay asked:You are right about folk forgetting the safety brief by the end of the flight but I can't imagine YOU making a smart-alecky comment, surely that's not something you're prone to, is it?Heavens, no! But it is something that I am sometimes...<ahem> "pprune" to. (Sorry.)

mass & bagagiste
6th Dec 2003, 13:47
In a situation where the helicopter hits the ground/water and autorotation hasn’t sufficiently slowed the descent/impact rate its going to make little difference if it’s a lap strap or a 3,4 or 5 point harness or if your seat is full back length or just up to lumbar region. All your rules go out the window, literally, because everybody is dead.

The seats are bucket type, bolted to the main deck and the skids may have some shocks to reduce ground resonance. The seats and harnesses on small helicopters, civilian or parapublic are a minimum requirement to comply with safety regulations and as has been said a design compromise. Weight saving and product cost is always going to be more of a priority than safety with operators. Compare the engineering in a Martin Baker crash resistant seat and crumple zones on combat helicopter hulls. The effort that goes into ensuring crew survivability is of another magnitude.

True, when your family of sightseers come cantering hesitantly in a stooped position to embark the helicopter, the noise and downwash & confusion of this new environment makes it difficult for a novice to figure out a 4 point harness, which means that someone has to show them. Twist to release four point seems to make people feel more secure than some airline style lap buckle harness.

I wonder if they made it mandatory to have crash resistant seats and 5 point harnesses, if they would allow more heliports to open in London. Kind of like a compromise?

WLM
6th Dec 2003, 15:08
I think we may be diverting from my original question here. I personally feel safer with a four point harness.
In some posting above, comparison made between aircraft and motor vehicle, is a little unfair. An aircraft travels at a higher speed, and height of course; a sudden decelaration or even abrupt stopping, ends with serious consequences.
Your average motor vehicle may travel at say 50-100km/h average most of the time, with a lap/diagonal belt quite adequate. However, a faster racing motorvehicle always has a four or five points harness. I wonder why......
So if an aircraft is faster, with a lot less crash protection around its occupants, to my eyes, SHOULD have the minimum of a four points harness. But eh, I am only the pilot here....:D

misterbonkers
7th Dec 2003, 23:40
my car goes as fast as a jetranger and it only has standard seatbelts!

I agree a four point harness is safer. But haven spoken to a a very experienced pilot yesterday, and learning he never tightens the shoulder straps on his four point harness anyway, it proves a point for the R44 type device.

There are pros and cons all round, and, as we've seen, some strong opinions.

Copter Driver
8th Dec 2003, 03:06
As far as safety I prefer the four point. In the R44 though, the shoulder belts are not able to be locked unless fully extended which is too loose for me. So they are gently pulling the lap belt up. Not a big deal but not as comfortable as a standard belt.

WLM
8th Dec 2003, 12:04
Copter Driver

Interesting reply from you since you work for F.R.:p Now seriously, is there a retro fit kit available for a four point harness available as mentioned in the above early replies?
Tks
WLM:ok: