Are single-engines safe over cities?

[Rushes]

This is all very interesting, but what about the role issue of the specific machine.

News organisations are about putting words and pictures together, ideally first, ideally live and ideally for extended periods of time.

This I imagine is one reason why the Police and some organisations have gone down the Twin route....for a 1 minute shot they get 1 minute of the subject matter they are interested in, rather than 15 secs of that, and 45 secs of the back of a building that is of little interest while the aircraft keeps up an orbit at suitable speed.

As we know some of the most filmed tube stations in London are stuck down some pretty tight streets....

[headsethair]

Rushes : a unique viewpoint (pardon the pun). So - you're saying that whilst a twin can hover, a single can't ?

Erm.

for a 1 minute shot they get 1 minute of the subject matter they are interested in, rather than 15 secs of that, and 45 secs of the back of a building that is of little interest while the aircraft keeps up an orbit at suitable speed.

Are you a helicopter pilot ? Have you noticed that twins also orbit. Just as singles also hover.

The main difference is the endurance. Whilst your average AS355 fully-loaded with 3 people, the tv gear and all that lovely fuel + spare engine, flying to Grp A, can just about do 1.5hrs between refuels - a good piston single like the R44, carrying the same load of 3 people and all the tv gear, can be on task for 3.5-4 hrs.

In a developing story/incident, which machine would you consider is the most useful ?

[Hughes500]

Just wondering if an R44 newscopter is 1668 lb, max useful load is 832 lbs. 4.0 hours of fuel at 16 gals an hour = 430 lbs. Left with 400 lbs, the 3 crew must be very light and with no extras in the machine ! Intersting auto at this weight from less than 60 kt airspeed when filming. It is intersting to look at the POH to determine auto range. The table was done by a pilot expecting an engine failure in ideal conditions for the certification process, therefore from 60 kts filming at MAUW will the ac land clear ?

[headsethair]

Your assumption and consumption need attention. You have assumed a weight which is not correct, and you have assumed standard fuel consumption. In reality we regularly achieve 3.5 - 4 hrs endurance depending on wind and power settings. The perfect filming speed (when not hovering) is also the max endurance speed.
One of the great advantages of the 360 nosemount is that we can spend more time with our nose into wind - we regularly get the shot by shooting at 180 rearwards and, so long as the downward angle is more than 30 degrees, no aerials or skids get in the way.
With regard to POH and glide capability - we have made substantial allowances for wind, airspeed and other variables. An R44 can easily glide for more than a statute mile from 1500-2000ft. And the helicopter configuration for certification is at MAUW producing a glide ratio of 4.7 : 1.

[Creaser]

Originally Posted by Hughes500

.... therefore from 60 kts filming at MAUW will the ac land clear ?

But previous posters were discussing hovering to get the shot, not flying at 60 knots.

Is it too simplistic a question to ask how much higher should a single engine heli hover to get same saftey margin as flying at 60 knots?


Creaser

[TiPwEiGhT]

Whilst we are on the topic of a certain R44, I have just bee looking at its website and the videos on it.

I am interested to find out how filming of the sailing was achieved on a CAT flight, or was it simply private? Just curious as my companies AOC clearly states that the R44 must remain within safe autorotational distance of a suitable landing site.

Thanks,

TiP

[2Sticks]

I'd been wondering how an R44 could legally film Wembley stadium from what seemed like quite close on the national news several weeks ago. Now I know (or think I know!!)
2Sticks

[headsethair]

Tip: not a CAT flight. See here.

2Sticks: that video is on the website, but probably too small to show altimeter reading - 1500. The "seemed quite close" is an interesting statement - what gave you that impression ? The camera with its 42X zoom ? Flying Special VFR at that part of London permits 500ft by the way - but we didn't use that advantage. Don't need to.

[CYHeli]

S/E V's M/E ENG

In Melbourne (Oz) at least one news agency has gone to an AS350 over their old AS355. Greater payload and good dependability.

Mind you, the only real engine 'failure' that I have ever witnessed is on an AS350 when a bolt cut loose in the compressor on start-up. Big bang, lots of smoke, no more noise. Good thing they were on the ground!

[rattle]

[QUOTE=headsethair]Tip: not a CAT flight. See here.

Only the CAA could produce that document that on the final page says "Page 8 of 7"!

[Rushes]

[quote=headsethair]Rushes : a unique viewpoint (pardon the pun). So - you're saying that whilst a twin can hover, a single can't ?


Headsethair, thanks for pointing this out, its a great help!

However, I am suggesting that a single engined machine, depending where it is, may not be able to achieve an autorotation to a safe place outside R160 from a standing start.... ie; a hover!

So I guess you have three choices in some of these circumstances.... stay close to the river, keep moving... or ideally BOTH!

However, i'm sure that you have this eventuality covered.....

So i'm now wondering which I would prefer..... the endurance..... or A PICURE in the first place!

[headsethair]

Rushes, you're losing me here. These Forum posts aren't much good at conveying irony. So - I'll have to use plain language and I hope you don't consider this to be patronising.

You earlier suggested that whilst a twin can hover, a single can't. That is not the truth. The hover performance (or any aspect of performance) has nothing to do with how many engines you carry.

You can ask many "scenario" questions that are more relevant than engine failure - and these come higher up the stats list.

Try "What happens when the tail rotor drive fails on a twin engine helicopter whilst operating low level over a congested area?" Then call the South Wales ASU for the answer. Or Mrs Jones who had an AS355 parked in her loft for a few days.

Try "What happened to the door handle of an AS355 when it fell off during a filming flight over south London ?" Answer - it's down there somewhere and hopefully it didn't injure anyone.

Getting preoccupied with engine failures doesn't reflect the real issues of flight safety. You only have to read the CAA quarterly Occurrence reports and you'll see what I mean.

[uncle ian]

Headsethair,

I'm still not clear exactly what you have gained permission to do. Can you fly within the Specified Area as long as you can land clear and, if so, how do you demonstrate that capability when the boys from the Belgrano would certainly disallow most open spaces (in central London) as they permit public access.

I have no axe to grind as I use both twin and singles in my own role. I am a bit mifffed, though, that it has taken a "personality" to sufficiently pressure our regulators to interpret the ANO correctly instead of making law which they seem to think is their proper role. I've been at odds with them for most of my professional flying career with absolutely no success whatever.

Incidentally, my current campaign with them is over age discrimination. Anyone out there in their late 50's NOT want to stop single pilot PT at 60 please contact me

[Huskie]

The R44 is a wonderful helicopter with excellent engine off characteristics but an engine failure from a 1000' hover in still wind conditions will offer no glide distance. In fact you loose 300’ to 400' before you gain sufficient forward speed to develop enough potential energy to conduct a safe landing. The area directly below is where you will end up.

Most ENG work is conducted at heights between 750’ & 1000’ at slow speeds in and out of wind i.e. orbits. For built-up areas I believe this profile to be the domain of twin engine helicopters.

Despite contra belief, engines do stop. Emergency landings are also conducted for reasons other than engine malfunctions. If the river Thames offers the only law abiding place to land in the event of a single engine helicopter emergency one has to consider the consequences of alighting into water with or without floats. At best you will go from being a heli to a directionless boat hitting the nearest bridge or barge to at worst becoming an ineffective submarine!

The reduced operating margins of the R44 over a twin squirrel is of great benefit and they do have a place in the video world but personally I would be very uncomfortable flying an R44 in a low level build up area. AS355s undoubtedly offer more performance and safety for me, my cameraman, passengers and people below. On this basis cost should not be compromised.

[headsethair]

I'm still not clear exactly what you have gained permission to do. Can you fly within the Specified Area as long as you can land clear and, if so, how do you demonstrate that capability when the boys from the Belgrano would certainly disallow most open spaces (in central London) as they permit public access.

OK. I have a feeling this is becoming more of a saga than necessary. First, let's take the celebrity factor out of it. Because I have. Then simply read the rules as they are currently written. Nothing's changed - except a myth has been kicked into touch.

With regard to "where to land" - well that too is obvious from the rules. The only requirement is to land without endangering etc. and to "remain able to alight clear of R160". Again, nothing has changed.

Our/my research was substantial and the docs alone would crash the pprune server. The critical piece of paper is Statutory Instrument 2005 964 available from the Cabinet Office website here.

This is the only "rule" that matters - it's the foundation for all connected rules issued by any other body. The only thing that changed was that SI 2005 1110 removed R160/Specified requirements from Rule 5 and placed them into 964.

Huskie: I disagree with you on the heights for ENG work. There is no need to go lower than 1000ft and most of what we do is around 1500-2000. Let the camera do the work. I also take issue (sorry) with your claim that the AS355 offers better performance - are you another one who believes that 2 engines give better performance than one ? I urge you to quickly do some W&B MAUW calcs and see the truth. Even Eurocopter say that the single AS350B3 has better performance than the twin AS355. Talk to the pilots.

And you're also wrong on your reading of the requirements for R160. It is only required that any helicopter suffering the failure of a power unit can alight clear of R160. No other emergency would preclude a landing inside R160 for any helicopter, whether single, twin or triple.

[Rushes]

Headsethair,

I can't see where I actually said that single engined machines couldn't hover , please go back and read my initial post!. I was simply trying to make the point that in order to achieve a safe forced landing from certain positions over a built up area, it would be beneficial to be moving in the first place, it's always nice to have some energy to convert. I do understand that the R44 glides well, you've read the POH so I know your well aware.

Hovering over the open countryside your options would tend to be greater.

So I make the assumption that a single engined machine is more limited than a twin over a congested area... Its that simple!!

There are some fantastic single engined platforms, but there is just a little more flexibility with the twin in certain circumstances.... is this so hard to understand.... or maybe just admit?

ps: I have no prejudice...single or twin, i just believe that everything has its place, and that we do not just have the legal issues to consider, but the moral ones as well.

[John Eacott]

MBJ is well aware of what we can achieve around Melbourne, so I'll pass on the main issue that he raised, but HSH appears under assault from some who don't seem to have had the pleasure of operating some of the better stabilised systems around. We operate two R44 Newscopters, and other than to change the dynamics of the shot, nearly all our work is around 1500ft or higher. This photo shows well the quality of the image from 1350'

[Huskie]

Headsethair: Thank you for your response. Please don’t misunderstand me with regard to performance. I am suggesting that in challenging weather conditions the handling characteristics of the AS355F1 over an R44 are preferable. Sometimes the pilot has to work very hard to complement the cameraman. I agree 1500’ to 2000’ offer good pictures but the weather doesn’t always allow this.

[headsethair]

OK. My last response I promise.

I am suggesting that in challenging weather conditions the handling characteristics of the AS355F1 over an R44 are preferable. Sometimes the pilot has to work very hard to complement the cameraman.

Huskie:

in challenging weather conditions

. Hell - what a generalisation. As I've previously stated, the nose-mount on the R44 ENG allows us to keep the nose into wind whilst still getting the shot. What could be safer than that ? Sitting over Scotland in a 50mph wind is one of my favourite places to be - that's 50mph of airspeed if we need it.
What machine would I rather be in crosswind ? Not the AS355 for sure. And definitely not a 206, while we're at it.

I agree 1500’ to 2000’ offer good pictures but the weather doesn’t always allow this.

If the cloudbase over a congested area doesn't allow 1000ft above the nearest highest object within 600m, then you can't go in any heli without an Exemption (unless flying under Special VFR and then you can use the 500ft rule - but why would you need to go that low if you've got a great camera with a professional operator?).
Rule 5 does not discriminate between numbers of power units.
And if the "weather" is pants, what pictures will you get in any case ?
And another aspect - the live link. We have the ability to get our pictures and sound over 100km. But to achieve this distance we need to watch our height - good as the new digital links are, even they can't defeat curvature of the earth to any great extent. In reality, getting our output live to W12 from, say, Milton Keynes needs 2000ft altitude.
That's it from me. This started as a simple response to MBJ and ended-up in the Cabinet Office. I love this place (pprune) - but I am not getting my work done.

John Eacott: we've never met, but thanks for your experienced support. It sometimes feels a bit cold in these parts, if you get my drift.

[Flingwing207]

Here's a little more support, Heads-

It takes about 400' of vertical descent to get an R44 at MAUW up to recommended autorotational airspeed (and RRPM) after an engine failure in a zero-airspeed hover. Push the lever down, as soon as the horn stops, push the cyclic forward as rapidly as RRPM will allow. Since most ENG work has a little headwind, you can reduce that altitude figure slightly. So from 1,000' AGL, you have your airspeed with 600' left to go, or put another way, you can put your spot where you want it simply by how slowly or rapidly you accelerate your airspeed.

It's very easy to keep forced landing areas in reach (as long as the areas are available at all) while positioning your ship, as long as you put safety first, picture second. With the great equipment mounted on most ENG helicopters, the camera op will have no trouble getting a shot as long as the angle is right, giving the pilot a lot of choice about altitude and distance. (BTW, I work as back-up in a 206 in both positions, pilot or camera op.)

As far as an engine failure goes - as folks with a lot more experience and education have pointed out, it generally isn't an engine failure that causes ENG (or most) accidents (ignoring the air in the fuel lines problem, which affects you no matter how many engines you are swinging). For the slightly (and I mean slightly) increased risk a single engine might create, the R44 will give you back reduced risk via almost no chance of LTE, excellent cockpit visibility, very low pilot workload, excellent fuel endurance.

Now I will say personally it makes me nervous to have that much power going through that somewhat cheap Robinson belt-drive system - in fact, on the R-44, that fails at a much higher rate than the engine, and usually with more dramatic results (an piston engine will usually fail somewhat gracefully). So do I think the R44 is a perfect ENG ship? Nope. But it is no more likely to cause a problem than ANY eng ship, single or twin (for what that's worth).