terminus
much truth in what you say with a little muddled thinking also:

2 ditchings in GoM: 1 was just an ordinary landing due Engine Failure - proving that 2 engines were not required in that case.
The other I don't know the cause of but it appears that it "struck the water" , maybe engine failure but unlikely if you have enough energy to 'strike the water' (and damage the helicopter so badly) then you probably have enough energy to flare and land gently. Was the second one and engine fail? Anyone know yet?


"Saying that components on a S-92 or EC225 are more stressed is garbage."
It is true that it becomes less important at bigger scale. It is very true for the lightest twins and progressively less significant for larger machines where the payload wasted (or invested, depending on how you see it) by carrying spare engines becomes a smaller proportion.

but if you spend payload on something not neccessary then it does cost you margins elswhere.

For example: If it were mandated to carry 500kgs of Lead (Pb) then clearly this would impact not only the margins of other critical components but also cause more time exposure of tailrotors (etc) per payload.mile, fuel reserve etc etc
If the 500kgs of Lead were useful to the extent that it was worth the downside then it would be an improvement. So it is not garbage , although it may not be highly significant.

Muddled thinking, only in your mind. My thinking is clear.

There are multiple reasons it may have "struck the water" and I agree that engine failure is not necessarily the most likely scenario. Same operator, 2 in 2 days, not good. Even the "successful" ditching is a problem, now you have people floating in a raft requiring rescue, way outside most OGP company risk profiles.

It may have been a mechanical failure, surely unlikely in such an unstressed machine with only one engine? It may have been crew error?

But, had it have been an IFR twin, it would have probably been operated in such a way that contact with the water would be minimized.

The argument in question (from AnFI and others) is that there is no justification for a single/twin distinction. Therefore, those operations would be equally safe, and acceptable, in a 206 (or 205, 214?, if you need more seats) as a Puma. So yes, regardless of why one was in those situations, they are relevant.

Interestly, as a contractor for a military customer, they were adamant we had 2 pilots to carry pax, but as long as the performance requirements were met the number of engines was unimportant.

Ultimately, all these rules are legacy items. Relics from decades past, fatal accidents not forgotten, and group perception. The fixed wing industry has saddled helicopters with reams of inappropriate legislation (such as the emphasis on numbers of engines as the penultimate measure of a safe design) and we will have to deal with it for some time! But yes, I still prefer to fly a twin. OEI RTB is less stressful than an auto. I've done both, having lost the use of an engine in the 22/500/412/76/332.

Solely for AnFI: if we are mandated to carry 500 lbs of lead by regulation, and the MGW of the type is unchanged, then I lose only payload available and the components are no more stressed. If a design is changed to increase MGW by 500 lbs to compensate then yes, there is more stress (and likely new components). Designers face many hurdles and the number of engines is one tool in the arsenal of compromises.

Finally, all the stats in the world trolled from endless google searches won't change the fact that it is all bu!!$hit. A pilot of a single is flying his aircraft with a different mindset and in a different role than the pilot of a twin, for a multitude of reasons (regulation, cost of operation, environment, sanity) and so the stats are heavily slanted!! Happily [hopefully] the ones who make the real decisions understand this LOL!

Fly safe, make sound decisions, and come home at the end of the day!!

Hi P&A

good points but the 500lbs of lead does because the payload is cut and so either more trips need to be performed to provide the same transport capacity. OR another way to look at that is: If the 500lbs of lead is removed but the payload is not increased then the critical components are working less hard. a bit perverse true, but true non the less...

They could run Twins with less 2 pax and achieve a similar effect Cat2e could possibly remove the e if only ONE pax were carried - but would it be worth it in extra runs? 10 runs with 1 pax or 1 exposed run with 10 pax?

I need two engines in my car - I'm worried about being stuck out on the hard shoulder if the engine stops.... Doh!

Wow, AnFI, that has to be the most idiotic comment I have ever seen on Pprune. Obviously the concept of any system redundancy is completely lost on you.

Off to the "ignore" box for you.

Interestingly, an armada of 8 French TV helis popped into Redhill yesterday, for a top up on their way from France to Yorkshire for Le Tour, all single Squirrels. Should be fun when the race gets to London !

.
That kind of single ? :

All (2) helis with cameras are twin ;)



http://nsa33.casimages.com/img/2014/...1149597204.jpg

TC suggests the "Almighty Dollar" is behind the FAA and NTSB decision on the 737 Rudder problem.

Have not many here argued that is the exact same calculation the Oil Industry and Helicopter Industry enter into when decisions re Safety are made?

When the Certifying Agencies (FAA, CAA, EASA, MOT, CASA) use a definition of "Most Unlikely" (or whatever the term is for a calculation of an event occurring) that would absolutely and without doubt lead to the destruction of the aircraft (killing the occupants), are they not doing exactly the same?

It goes on everyday in this World wherever Helicopters are flying.

If you climb into your Cab at Aberdeen, a PAS Unit, or in the GOM, you are accepting that concept yourself as you know Helicopters are not a perfect science and never will be. You gamble your Life for that pay check.

So how about all y'all quit the Finger Pointing.

Ah, apologies, didn't see those two arrive. So the singles with cameras are.... what? ;)

Redhill

Edit - I've been corrected, the pods on the singles are Relays for the downlink, ooops

.

;) Yep, and the others single are for VIP flights.

.

Fortunately Term Mos can't read this:

He said "Obviously the concept of any system redundancy is completely lost on you."

but he really is an ingnorant fellow .... redundancy is a concept but reliability of a simplex system is better, obviously.

use the weight spent on a 'redundant' (the clue is in the word) system to make the single system unlikely to fail, then the 'redundant' system (that is REDUNDANT and just consuming payload) is not required - doh!

how much 'redundancy' do YOU have in your car? Is it reliable?

Now that's a schoolboy howler if ever there was one! :D

hmm that is baad but just a slip of they keybored in this case

that is part of the problem - the world is run by people who can spell at the expense of people who understand Noether's Theorem