What is it with people and this manic drive to make everything risk-free?

[Peter Miller]

David raises an interesting point. He mentions the large model problems.

 

Back in the 80s I suggested in my column "The engine Bay" that the really huge models being built should be inspected in the same way that full size homebuilts are.

 

Dr Jeremy Shaw (Leading light in the large model scene in those days) went berserk. I kept his letter for years. The idea was totally ridiculous etc. etc.

 

Correct me if I am wrong but isn't it a requirement that giant scale models while under construction these days?

 

The great majorityy of contributors to this thread seem to agree that the buddybox is a definite safety need for the reasons stated. i.e. you don't know where the model is, if things go wrong picking it up visually after removing the head set will take some time. The model could easily fly out of range while the pilot is not really sure just how far away it is.

 

In view of that, I am sorry but the idea that flying FPV alone fills me with horror.

[Lee Smalley]

david your preditions are frankly on a par with Nostradamus  if all you can see is directly ahead of you how can it possibly be safer than a complete field of view!! when you are doing a loop how can you possibly see when to pull out of the loop to avoid the ground or obstruction on the patch (if a member of the public wanders out into the path) and how do you know when a stall is looming

 

i don't see why FPV should be banned but what is wrong with flying with another person (as additonal pair of eyes) in built up areas, they can do what they want in the middle of no-where!!

 

lets not get to the point of making statements just to wind people up guys keep it sensable and friendly  

[David Turner]

In reply to LS.

 

The pilot's vision is not restricted to directly ahead. Cameras pan and tilt in sympathy with the pilot's head movements. Just like full-size.

 

And, you speak of a complete field of view. Is that what you have when you fly LOS? No, you have a 2-D image with practically no perception of depth.

 

Angle of attack indicators are a reality and, if fitted, make the FPV aircraft less likely to be stalled than your LOS aircraft. Ergo...safer!

 

It's indisputable that pilot error is the dominant cause of model' crashes; and it generally involves loss of control following a stall. Why haven't you something similar fitted to your model?

 

There is no requirement to use a buddy-box...the proposed requirement is that the PIC remains in visual contact with the aeroplane, sufficient to take control. So, the FPVer may have hold of the transmitter and pass it to the "visual pilot", who is the actual commander.

 

 

Edited By David Turner on 26/11/2009 18:55:36

[Kelly]

You can always practice on a flight sim such as FSX with virtual photo scenary of your flying site and surrounding area,less chance of getting lost,this is my site and surrounding areas

 

[Lee Smalley]

so the camera rotates 360 degrees does it ?  and everyone has 2 d vision fpv or not

 

"""It's indisputable that pilot error is the dominant cause of model' crashes; and it generally involves loss of control following a stall. Why haven't you something similar fitted to your model?""""

 

following a stall!! not in my models !!!!

 

my crashes this year causes  

 

1 lost radio

2 mid air 1st in 20 years

3 clipped grass on low pass

4 general lack of ability in number 3

 

so you can not really generalize that the stall is the dominate cause of model crashes, actually come to think of it i can barely think of a single crash at our club that has be due to a stall so again a claim that just does not hold up

 

and please dont nit pick a buddy box type approch was what i was refering to

 

again it seems to me people are making comments intending to illicit a reaction,

 

I personally can not see how a lone FPV flyer can ever be safer than a standard line of sight and again i never want to see a lone FPV flyer at the club im a member of!

 

im sure that FPV ers can be accomodated but untill people are happy with the tech and methods then i think the buddy system is the best they could have expected and really they should live with it until they can prove otherwise

[Lee Smalley]

oh and by the way angle of attack indicators have nothing to do with stalling really

 

Edited By Lee Smalley on 26/11/2009 19:20:36

[Olly P]

Lee - actually they do, but only if linked to a/s indicators....

[Lee Smalley]

but that was not the point was it!!! angle of attack indicator have nothing really to do with stalling you can stall in level flight its completley off topic so i will not go on

[David Turner]

Posted by Lee Smalley on 26/11/2009 19:18:52:

 

so you can not really generalize that the stall is the dominate cause of model crashes, actually come to think of it i can barely think of a single crash at our club that has be due to a stall so again a claim that just does not hold up

 

 

 

OK, stalling is a non-issue, if you like.  But, it's even less of an issue when flying with an A of A indicator.

 

The cameras generally pan 180 degrees and tilt up to 90 degrees ( I think). This is comparable to the view that is available to the pilot of a full-sized aircraft...because he is constrained by harness, esp when performing aeros.

 

There's no way to legislate against lack of ability or simply "flying into the ground", I guess. These come into the "Don't do nuthin' dumb" catch-all of the ANO.

 

The buddy-box "confusion" is worthy of note  because it's an indication of the wider lack of awareness of the actual proposals. Like it, or not, there is NO requirement to use a buddy-box. In fact, in view of the BMFA's well-publicised warnings about the unreliability of the buddy-box system, it's probably as well for the FPVers to avoid using them.

 

I fully agree that the FPV community should live with the ANO until it can prove itself capable of long-range flight. But, I think that the relevant technology already exists, or is on the cusp of becoming available. So, I don't expect that it will be long before the FPV community begins to lobby for change.

 

I can't understand why there should be such hostility towards an emerging facet of aero-modelling.  Could someone explain that for me?

 

I'll let someone else take up the issue of Angle-of-attack indicator. Someone a little more diplomatic, perhaps.

 

Edited By David Turner on 26/11/2009 19:42:18

Edited By David Turner on 26/11/2009 19:44:40

[Lee Smalley]

unreliability of buddy box systems ehh!! am i missing somthing its been used in clubs to teach learners for years, when did it become unreliable

[David Turner]

WRT buddy-boxes.

 

I may  be mistaken, but I seem to recall that the BMFA published a warning in its magazine. There had been instances of switches becoming jammed and of leads becoming disconnected...they are just push-fit, after all.

 

I've certainly heard of leads becoming dis-connected.

 

Hardly ever use them, myself.

[David Ashby - Moderator]

Folks, remember that there isn't an argument to be won or lost here - just state your thoughts. Remember also that some posters prefer to antagonise, don't rise to the bait.   

 

Edited By David Ashby - RCME Administrator on 26/11/2009 20:45:18

[Biggles' Elder Brother - Moderator]

Hi David,

 

I don't think I've heard anyone saying they are "anti-FPV". A few (including myself) have said its not an aspect of the hobby they feel drawn to, but I think everyone agrees that those who do want to do it should have the opportunity.

 

But I think what a lot of us are saying is, as things stand, the FPV guys should consider themselves fairly generously dealt with by the CAA. The requirement that FPV, let's face it a new, largely untested, development in hobbist's hands,  can go ahead provided a "LOS co-pilot" is available to take control is a sensible first step. You might be right, who knows, one day FPV might prove to be so safe that solo FPV is permitted. But based on where we are today, the technology available at the moment and the relatively low level of experience with that technology a co-pilot and staying within static visual range seems the sensible (and quite liberal on the CAA'a part in my opinion) option.

 

BEB

 

PS Just on a matter of technical accuracy, LOS flyers do see in full 3D provided they have two eyes and hence stereo-vision! I agree you would not always think so to watch all of our colleagues, but it is non the less a fact). On the other hand an FPV pilot's view, through a monocular camera, is strictly 2D only and contains very limited depth information - confined only to judgements made based on relative size of known objects. An FPV pilot can only guess the relative depth distance between two points in his field of view - and a crude guess at that. I'll make a prediction now....true FPV will only really come of age when we have true 3D video - which is not as far away as you might think!

[Peter 'Ivanna Crashalot' Savage]

Peter, i did not mean getting a buddy box system is cumbersum, it is the fact you need a person standing next to you while you fly, holding the trainer switch which really isn't the most comfortable thing to do for 10-20 minutes, that and he has to have constant sight of the model. With buddy box you do still need another transmitter which if you don't have will set you back, and if you don't have another person to go flying with you are screwed.

 

With some of the LMA models it must end up being cheaper to actually buy a full size aircraft and learn to fly!

 

I would thinkn if it is just a thing about crashing during learning how to do it, you could have buddybox support while you get used to using it.

 

Is it really any different (maybe on a smaller scale!) to these people sitting in a room with a joystick in front of them flying these Predator UAVs?

[David Turner]

Depth perception is a complex subject. As far as I am aware, stereoscopic vision becomes ineffective within about 18 metres. Beyond that and out to a range of around 180m, a number of other visual cues provide information which enables the person to perceive an object's range.

 

Beyond 180m, depth perception becomes a very woolly prospect, indeed. A model, against a background of sky, offers few perceptual cues to the pilot. The main one is its apparent size. That's one reason that people land in trees.

 

3-D vision is relatively unimportant to the full-size pilot. Most of the threats to his aeroplane lie far outside the range of effective depth perception. And it is a fact that pilots have tremendous difficulty with the task of "see-and-avoid"...partly for these reasons.

 

There is a good deal more to this subject than the possession of two good eyes. Anyway, some optical professional might chip in with more information.

 

I agree that the "camera" view does not provide stereoscopic vision, but it does provide a range of other visual cues which are effective for more distant objects. These cues would include details of surface' texture, colour, relative size and parallax.

 

I'm not trying to claim that a camera-eye view is as good as the human eyeball. But, I do claim that the LOS flyer often has little or no idea of the range of his aircraft.

 

The LOS flyer does not represent a "Gold Standard" to which all FPVers should aspire... his point of view is, itself, fundamentally flawed and could be improved upon.

[Peter 'Ivanna Crashalot' Savage]

You are not really going to be flying FPV with objects in front of you so i do not see how depth perception would come into that, from the FPV videos i have seen it has been quite obvious how high they where and whether they were about to hit objects. If you were worried you could even put two cameras on the plane and place them a little bit a part to give stereo vision.

[Martin Harris - Moderator]

Posted by Lee Smalley on 26/11/2009 19:34:06:

but that was not the point was it!!! angle of attack indicator have nothing really to do with stalling you can stall in level flight its completley off topic so i will not go on

 

 

I'm afraid that an AoA indicator is the ONLY reliable instrumented source of information that you are about to stall.  Also, we don't experience any of the physical effects on the airframe (e.g. buffet, controls going light) which herald the onset of a stall in our models, either FPV or LOS, and we don't get feedback on these effects from the model(well not yet, anyway).

 

The AoA is the difference between the chord line of the wing's aerofoil and the airflow hitting it. A stall occurs when you exceed the critical angle of attack.  It isn't related to pointing the model straight up, straight down or anywhere in between. 

An airspeed indicator will not reveal the stalling speed EXCEPT in co-ordinated flight at 1G .

 

I'm not sure why Olly needs the AoA indicator to be used with an ASI but the bottom line is that AoA IS the be all and end all of stalling!

 

 

Edited By Martin Harris on 27/11/2009 01:33:17

[Simon Dale - Firstpersonview.co.uk]

3D cameras specially designed for FPV flying are available today here: http://www.firstpersonview.co.uk/index.php?main_page=product_info&products_id=173  These give excellent depth perception for close up flying (formations, close to trees, landing, etc).  As David Turner says above beyond that 3D vision is a blurred (excuse the pun) subject.  Airline pilots seem to manage to land on their simulators OK...

It is a shame that the CAA didn't consult with any single FPV pilot when writing their new proposals or we could have shown them these 3D cameras and many many other innovations of which they no doubt unaware (the GPS powered On Screen Display for instance which tells the pilot how far he is from home and in what direction, and also battery condition, radio gear signal strength, etc).

With regards to the dreaded video link failure which people get hung up on I think this is very like RC link failure.  In fact slightly better.  If your RC link fails you're skuppered.  Game over.  And possibly (depending on failsafes, etc) you've got the throttle open.

In the unlikely event of a video failure when flying FPV you can cut the throttle, remove your goggles, find the plane and land.  Or, in the worst possible case, you can't find the plane (the vast majority of FPV pilots fly motor-gliders - something like an Easystar bimbling around at 20mph or less so I find this unlikely) and you lose the model.  No worse than an RC failure.

Just like with RC equipment we must always ensure that we're using high quality equipment and range test before every flight.  Personally I fly the plane around LOS whilst recording the video for the first flight as a good test on everything. 

As with all types of equipment relating to RC modelling things can fail but the risks are reasonable and can be mitigated with a little thought.  The BFPVMFA guidelines recommend this kind of thing.  http://www.bfpvmfa.org/downloads/safetyguidelines.pdf

I've read through this entire thread and as is often the case on a forum like this there is a tendency for the tone to go in the direction of "It can't possibly be safe....and besides who wants to see the view from the cockpit anyhow...the whole point of modelling is to see the plane!".  May I say, respectfully, that there are also those people who are exclusively interested in flying from the cockpit view and simply can't understand the attraction of watching a plane from the ground!  Its no coincidence that a huge percentage of the FPV pilots that I speak to are also full size pilots (although the cost/ salaries ratio may also be a factor here!).

There's nothing quite like flying in formation, or mock dog fights with a pal, or flying through hoops on the airfield.

There is an assumption, usually by those whom have never tried FPV, that FPV flying gives the pilot and incredibly restricted forward facing view.  As David said above this is not the case.  The camera pans and tilts fluidly as the pilot's head does, just like in full size aviation.

The view from the cockpit has been used to fly conventional full size aeroplanes from the beginning and the 180/90 degree view from the cockpit has been proven to be excellent for this

Given the challenge of flying through two goal posts 200 metres away from launch I would rather fancy a pilot flying FPV than a guy flying LOS who is looking at the 2D side of his model from 200 feet away.  Lee Smalley: Perhaps if you were flying FPV this year you would have avoided the accidents number 2 and 3 on your list hehe.  From the cockpit its a damn sight easier to judge your position in relation to other aircraft than it is looking up, focused intentently on your own model from several hundred metres away.

Also, with FPV you have none of the issues related to reversing controls and "which way is the model heading?!"  From inside the controls are always the same!

Let me explain the position of the BFPVMFA in relation to the proposed changes to the ANO:

We accept and welcome the changes which ensure that flying a model aeroplane equipped with a camera must be done away from people and property.  All of our members are already fully aware of their responsbilities to fly this way and already do...(not least because interference from WiFi, microwaves, and cordless phones can spoil the fun! )

We welcome clause 98(2) which says that a pilot must be sure that the flight can be safely made before taking off. 

Article 74 of the ANO already makes it illegal to do anything which is dangerous and 98(2) above makes it illegal to take off if you're not sure that the flight can safely be made.  These two give the CAA more than enough room to prosecute the kind of idiots who won't obey any guidelines or rules that are put in place by the BFPVMFA, the BMFA, the CAA or any other body.

The vast majority of FPV pilots fly low mass, slow, foam airframes powered by electric - for example the Multiplex Easystar which is also a pusher.  The AUW of an Easystar with FPV equipment is around 1kg and even in the extremely unlikely event of impact with a human being, and even more unlucky event of it being on the head, it would be unlikely to cause death.  Obviously we are all aware that big IC powered aeroplanes, helicopters, turbines, etc are a different kettle of

• Quote

[Simon Dale - Firstpersonview.co.uk]

fish.

 

To limit the airframe to 1.5kg or thereabouts would seem to give the right level of risk mitigation (IE a very acceptably small risk - "2.5 Low risk" according to a risk assesment done on the CAA's template) whilst still allowing us to fly from time to time.

 

Personally if I couldn't fly FPV solo I couldn't fly at all.  My nearest "buddy" is 50 miles away and I don't own a car.  Can you imagine trying to organise his schedule, my schedule, the weather and a 1 hour delay in driving every time you wanted to fly (in a safe, responsible way in accordance with all of the good principles that we all have relating to RC flying and in accordance with the ANO)?

 

We will soon find ourselves in the very strange position whereby an FPV pilot can fly legally if so long as when he puts on his goggles he turns off his Tx...then its freeflight.

Edited By Simon Dale - Firstpersonview.co.uk on 27/11/2009 03:47:42

[David Ashby - Moderator]

Posted by Biggles' Elder Brother on 26/11/2009 22:47:59:

Hi David,

 

I don't think I've heard anyone saying they are "anti-FPV". A few (including myself) have said its not an aspect of the hobby they feel drawn to, but I think everyone agrees that those who do want to do it should have the opportunity.

 

David - just a moderator concern about the temerature of the debate.  

[David Ashby - Moderator]

Hi Simon, You're the chairman of the BFPVMFA - are you hopeful that the CAA will reconsider your case? Just out of interest what's the position in the USA? Are flyers there less restricted?

[Dave Bran]

OK, here's my 5p.........

 

Firstly, background reminder, I operate a twice weekly RC club inside a school, possibly one of the few to stick head above parapet in that environment on a very regular basis?

 

Re: Buddy Box Leads - they are designed (well, possibly designed, more like thrown together) from generally inadequate components with little or no thought to their security or longevity.  Yes, there is a problem, No, no-one is seemingly doing anything about it other than the odd Tx recall when it all goes REALLY wrong.

 

Re: FPV - I think the controls put in place are broadly sensible at this point in time. Development will no doubt be rapid.  The best people can do is to demonstrate a sensible approach and be patient.  I cite the Silverlit Piccooz Heli and only one year later the MicroTwister, infinitely better and much more controllable for the same money.

 

One more analogy for you though, when AC publicly pushed the boundaries of common sense on the M1, they triggered a reaction and a motorway speed limit which still exists today, despite vehicles being infinitely superior in handling and braking.

 

Don't put yourself in the position of  being the one to trigger a similar permanant situation. Don't buy "bargain" inadequate systems, and fly only where and how it's safe.

 

Got to go, feel like flying my FPV 90 size Heli over the Common, down the High Street and maybe chase a commuter train or two........................look for the video on YouTube later..............

[Olly P]

Martin - Stalling, AS and AoA are all inherantly linked. The stall AoA varies dependant upon AS - at a higher speed it is possible to maintain a higher AoA, however this airspeed will bleed off quickly due to increased drag. the critical thing is the lift co-efficient generated by the wing. I will dig out my textbooks later to remember the exact formula, but essentially it increases with increasing incidence angle until the airflow de-laminates, However the de-lamination will occur at lower angles at lower speed....

[David Turner]

You are correct in that Reynolds Number will affect the aerofoil's critical lift co-efficient. The easiest variable to adjust, with respect to Reynolds number, is airspeed. So, the wing is likely to achieve a higher angle of attack at higher speeds and at higher power settings (propeller-driven aircraft).

 

These phenomena are noticeable to the full-size pilot. I have seen a POH which specifically refers to the higher A of A which may be achieved during the accelerated stall, though it  claims that it is of no real significance. And there are instruments available which compensate for this effect and provide the pilot with an indication of buoyancy or lift reserve.

 

But, by and large, an Angle of Attack indicator will provide a reliable indication of a wing's proximity to its critical angle...esp. when the indicator is calibrated towards the "one-G" stall. That is, the indicator is calibrated towards the "worst-case scenario", so it will always tend to to elicit a "safe" response from the pilot.

 

There really is nothing that is as simple as it first seems, is there?

Edited By David Turner on 27/11/2009 09:52:15

Edited By David Turner on 27/11/2009 09:53:16

[Bruce Richards]

Someone asked earlier about the BMFA insurance policy. I asked the BMFA and the sent me a synopsis which I would be happy to send anyone if the PM me their email address. I have also asked for the full policy document but I expect I will be referred to the broker.