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View Full Version : A really stupid question: rear view mirrors


bugdevheli
15th Jul 2010, 01:12
Apart from dazzle from the sun, and a little extra drag, why are most helicopters not fitted with rear view mirrors?

spinwing
15th Jul 2010, 02:03
Mmmmm ....

..... Why Are Most Helicopters Not Fitted With Rear View Mirrors. ....


Probably because we are more interested in where we a going, and already know where we have been!


:rolleyes:




In fact we do use rear view mirrors when carrying out underslung external load tasks .....

piggybank
15th Jul 2010, 02:30
Worth asking I suppose, even if just for thoughts on it.

I remember in the 90's in the cojo seat of a Puma fitted with a bubble window it was interesting to have a look back at all the workings and bits turning, interesting for a short while and took a few pictures.

As to mirrors looking back I would assume there is no advantage, except say in dangerous areas that have UAVs slinking around.

212man
15th Jul 2010, 03:19
Having used them in Super Pumas, Bell 212s and S-61s, I don't think it's a stupid question! In fact, when you change to a type without them you feel 'blind' when on the ground, where once you could look behind at the loading and refueling activity etc. They also allow you to look behind for signs of fire, if you want to confirm a warning.

The only disadvantage I know is they allow ice to acrete which may then fly off in chunks!

SASless
15th Jul 2010, 03:41
Had an Army Colonel make such a suggestion one time in an Aviator's Safety Conference....said comment resulting from his opinion Rear View mirrors would prevent Tail Rotor strikes while hovering around trees, bushes, mountains....etc.

A very crusty old CW4 who had started his Army flying in Korea reckoned the Colonel was on to something....and opined that done right...with mirrors on all four corners of the aircraft the Colonel would be able to see the back of his own head if he tried.

Exit one very unhappy Colonel after the Warrant Officer chorus soundly applauded the old fart's comment!

EBCAU
15th Jul 2010, 05:47
At the risk of thread creep, but on the subject of T/R strike prevention, even the lower model cars are increasingly fitted with an obstacle detection system for reversing.
How long do Ppruners think it might be before we see something like this on our helicopter rear ends?
10 - 30 years?
:hmm:

mtoroshanga
15th Jul 2010, 06:53
They have it on some already, its called the tail skid.

212man
15th Jul 2010, 07:17
I know one major manufacturer is trialling it, so I would think within 5 years.

John R81
15th Jul 2010, 07:53
Rear view bullet camera would be my preference - no drag or icing issues, selectable on the scroll button for one of the screens, very little weight.

Bitmonx
15th Jul 2010, 08:18
I use the mirror every single time I take off into the hover and also before touching down.
Too many times have pilots got airborne with a sling attached to the hook but forgot about it......
Many times when landing in the bush, the skids may become snagged by a root or something else and a quick check in the mirror will assure you if the skids are free or not. The mirror becomes quite useful when landing on logpads or checking passengers when they unload the tailboom.

cpt
15th Jul 2010, 08:22
I also strongly believe a rear mirror is a very good asset, not only to watch what's going around the tail rotor, or on a underslung hook but also to help in decision taking when dealing with badly locked cowlings, smokes, sudden increase in vibrations, change in noise.... I remember having used a small rear mirror fixed on a broom stick just to look if the loads carried in side external baskets stayed in place....Of course the rear view bullet camera is a smarter solution as long as the vibrations on the tail section don't affect the visual and that the lens can be kept clean.

Senior Pilot
15th Jul 2010, 08:51
The original RN Sea King HAS1 didn't have a rear view mirror, but they were added (IIRC) about 1972. Checks required a visual confirmation that the gear was down (2 greens didn't cut it!), and it was difficult to get a Mk 2 or Mk 3 bone dome out of the sliding window to look. Hence the mirrors, which also became handy to check the intakes (pre barn door mod), etc. If they were still there, it could also be assumed that the engines were also attached ;)

Fareastdriver
15th Jul 2010, 10:15
Mirrors were initially fitted on British registered SA330 Pumas as a means of checking the build up on the snow dam in front of the engines. It was also invaluable for checking the physical situation around the engine cowlings in case of fire warnings, loose cowls etc. When the 332 Super Puma came along with their different intakes management and engineers decided that mirrors were unnecessary.
Then Doogal (RIP) had a double engine failure owing to ice accretion on both engines. Fortunately is was at several thousand feet so he had time to get them restarted. All the aircraft then had mirrors within a week.
I flew for a long time on an operation in China where there was a mix between British and Chinese registered aircraft. The G reg with and the B reg without. Personally, I was happier with mirrors. I had to use them in anger several times with regard to EFWs which helps to keep the heartbeat rate down. Conversely I never had a fire warning on one without mirrors but they were still reassuring if you had some strange rattle around the roof area.
I noticed that Bristow Australia still retained them for their operations when I flew for them.

Impress to inflate
15th Jul 2010, 11:20
Mirrors are the best thing fitted. I use them regularly, they have saved my bacon or given me a heads up on problems like open panels, ice build up, who is near the boot and 101 other things. I wouldn't be without them

topendtorque
15th Jul 2010, 11:23
A very good friend of mine who recently passed on, told me once that they would be a good asset for a Bell47. Oh Yeah, why?

'Well they are the only aircraft liable to get a bird strike on the trailing edge of the sinc elevator, as he pointed to a slight bend on mine.'

C.C.C.
15th Jul 2010, 12:24
http://i179.photobucket.com/albums/w283/CCairns_2007/Bristow/Miri_09.jpg
Do not recall checking a snow dam on the SA330J as they were fitted with a snow shield in front of the engine intakes, however on the AS332L snow accumulation in front of the air intake is a well known hazard after the double engine failure at Aberdeen on take-off due to a prolonged ground running/taxying in heavy snow.

If memory serves me right we originally had only one proximity switch to activate the cowls warning light on the AS332L, which would only operate if the dog house cowling was open (or missing - had one of those fly off before the mirrors were retrofitted) or the engine cowling on that side was open. Recall the late Ron Miles being told by Aberdeen ATC 'Do you know your engine cowling is open' on short finals in the early 1980s, that being the engine cowling with no proximity switch originally. And the mirrors had not been retrofitted before G-TIGD's tail rotor failure.

On the S92A we have no mirrors as the ice formed on them would affect the current icing clearance when it falls off into the engine intake, so it was fortunate that we had another aircraft taxying out behind us when our No.2 engine cowling fully opened prior to take-off.

Mirrors are thus very useful. Otherwise how do you check for signs of fire following an engine fire warning!

212man
15th Jul 2010, 12:36
Anyone from Sikorsky reading this thread........?

ShyTorque
15th Jul 2010, 12:40
I wish all helis were routinely fitted with rear view mirrors.

RAF Puma HC1s had them as an interim mod before Polyvalent intakes. We used them to look for ice, the intended purpose, but as others have said, invaluable for monitoring the condition of the engines - checking fire warnings, oil leaks, panel security etc. Not to mention the tail rotor and who is in your 6 o'clock!

We were horrified to see the engineers removing them a part of the 'PIP' intake mod. scheme. We asked to retain them but were told it wasn't possible!

Dan Reno
15th Jul 2010, 16:36
http://i599.photobucket.com/albums/tt80/DanReno2/02.jpg


The SH-60B uses it for the MAD operation (see pic) and the H-53 D & Es use them for mine sweeping.

JohnDixson
15th Jul 2010, 21:34
The cockpit controllable mirrors for minesweeping can be seen at this site:

http://data3.primeportal.net/hangar/michael_block/mh-53e_sea_dragon/images/mh-53e_sea_dragon_37_of_43.jpg

Basically not very different from the RH-53D mirrors.

Thanks,
John Dixson

HOGE
15th Jul 2010, 22:12
Rear view mirrors. Great for checking undercarriage, engine intakes etc.

There I was, P2 in an S61. Adjusted the mirror, which promptly snapped off and departed down the left hand side of the fuselage at 110kts

Cue one very long second as I waited for the sound of the mirror entering the tail rotor....


Fortunately, it missed.