Question for aircraft electrical sys smarty pants

[piperboy84]

Looking at putting the following unit on my aircraft but I notice from the install diagram

http://www.seatoneng.com/docs/MaxPulse/2014/9150-001G.pdf

Wiring diagram on page 3 of 5 of the linked PDF

That this unit is connected prior to the existing landing light switch which I presume is what the "X" denotes and I assume removes the need for the existing on/off switch. For aesthetic and keeping my switch bar uniform I do not want to eliminate or remove my landing light switch, do you think it's a problem to wire this downstream of the landing light switch and just leave it ON and have this unit control the flash, solid or off control. Is there an issue with grounding when configured as I propose.

Factory wasn't much help.

[Jan Olieslagers]

Reading the pdf, I understand the device you wish to add is a dimmer for the landing light(s)? If so, I am confused about the "flash, solid or off control" bit.

Be that as it may be, I cannot see any issue with leaving the existing switch in place; and you have every liberty to power your new gimmick from before or behind said switch.

Neither would it make any difference to grounding - the text clearly states that the 'ground' is only used as a reference. Which also explains the use of the smallest size crimp-on connector: "red".

BTW what's the relation to "smarty pants" ? Made me think quite far from aircraft electricals...

[[edit]] I have not the slightest idea about official requirements ; on an "Annex 2" plane there should be no problem, perhaps, but how's about a proper certified aeroplane?

[piperboy84]

It's a selectable fast, slow selectable pulse landing light (not a dimmer) I want to use in an attempt to scare the deer and birds off the airstrip when landing at dusk and as winter approaches with it getting dark earlier.

Was thinking about adding a matching landing light to the other wing then this unit staggers the pulses which would make it more noticeable on approaches.

The unit is all FAA'd, PMA'd STC'd up the ying yang so is fine on a type certificated aircraft.

[tecman]

The 'x' is the usual symbol to indicate breaking a circuit, e.g. by removing a wire or cutting a PCB track. You could power the flasher unit downstream of your switch as you suggest but you should make sure to break the existing switch-to-light circuit. Otherwise, your landing light switch becomes a 'bypass' switch and, not knowing the details of the flasher unit, it's inclear whether it would appreciate that configuration.

One advantage of doing what you suggest might be that you can leave the fiddly rotary switch in your favourite position and control the landing light with a single flick of the rocker switch. But I daresay there are placarding requirements and maybe STC (or whatever) compliance factors to consider in a certified aircraft. Even if you did the factory recommended installation and left the landing light switch physically in place, I guess you need to placard it as u/s.

It might all be bit disco in practice! Any evidence that flashing the lights scares livestock?

[gemma10]

By leaving the switch in-situ you will be able to override the flashing unit,as it remains in parallel with it. Leaving the switch in the off position will thus allow the flashing unit to be operative. We are talking pulsing approx 10 amps here so make sure all connections are A1 and size the cable accordingly. If you go down the route of adding another lamp on the other wing then the switch, wiring and CB will need upgrading in rating. With this high speed pulsing I`m not sure about the life span of the lamps.

[Jan Olieslagers]

With this high speed pulsing I`m not sure about the life span of the lamps. I wondered the same thing. Actually the higher frequencies would be best for incandescent lamps, they would leave no time for the filaments to get cold. On the other hand, LED's would have no issue but I would be concerned about elco's in the LED driver circuitry.

Besides, I support the misgivings about the effect of such a flasher for the given purpose. Better install an airhorn, or even some kind of shotgun. ;)

But flashing the landing light(s) does look like a good help to "being seen" especially when flying the circuit.

[abgd]

Is it meant for aircraft? I would second the concerns over the life of non-LED lamps. If it's flashing slowly enough to be visible then I would expect a reduction in their lifespan.

The other concern would be the effect on other systems e.g. voltage fluctuations to the radios. I've seen one system that diverted the current alternately to the lamp or to a dummy resistor in order to prevent this. Using 2 x landing lights and alternating them could be a more elegant way of doing this.

[gemma10]

I think an airhorn would be more suitable too. I also wonder with all those flashing lights anyone looking up might construe that " That guy up there looks like he`s got a problem". Do deer have good hearing ?

[Jan Olieslagers]

Using 2 x landing lights and alternating them could be a more elegant way of doing this.
And that facility is offered by the device under discussion. At rates of 44 or 88 or 120 times per minute.

Do deer have good hearing ?
Better than mankind, I should think - not hindered by any factual knowledge. Generally, human senses seem to be not the strongest in nature. But I also feel the beasts would soon get used to the sound. Wasn't the traditional way of doing it to always make a low pass, than a circuit, perhaps repeat, and only then to land?

[piperboy84]

I figured the pulsing would burn out the old 4509 landing light pretty quick so have ordered one of these as a drop in replacement

WHELEN PARMETHEUS PLUS LED REPLACEMENT 14V LANDING LIGHT - PAR 36 - P36P1L from Aircraft Spruce (http://www.aircraftspruce.com/catalog/elpages/whelenparplus362.php?clickkey=346133)

Wasn't the traditional way of doing it to always make a low pass, than a circuit, perhaps repeat, and only then to land?

Yes, I do that sometimes, but I have landed and only on roll out have I noticed the buggers faffing around at the end of the strip.

The strip is bounded on one end by a nature reserve/bird sanctuary and the municipal dump on the other, both obviously magnets for all kinds of birds at low level especially during the days they are dumping shyte.

[tmmorris]

.303 and a ghillie suit? Plus some long nights waiting for the buggers.