Digital display of oil temperature and pressure?

[Richard Mole]

I'm looking for a very light-weight digital display that will accept the inputs from standard automtive VDO senders ?

Stratomaster do various dispaly units eg the E3 is about 100g plus connectors.

Does anyone know of something lighter by any chance?

[Brian Hope]

Hi Richard, I don't think Belite do an oil pressure/temp guage but I spoke to them at SnF and believe they are up for receiving suggestions on increasing their range to meet market requirements. Might be worth contacting them. Saw TREK arriving late in the day for Expo on Friday, sorry not manage to see you there for a chat.

[macconnacher]

Richard in the old days we used an MG Midget oil pressure/water temp analogue guage which was small and cheap - no doubt still obtainable via MG Car Club.

[Richard Mole]

Paul, yep thanks. I do like some of their stuff a lot eg fuel level display. And the g meter seems pretty neat too, as is the little voltage display.
Brian, sorry to have missed you Friday. I have contacted Belite and they tell me that they plan to make a double CHT display (they presently do a CHT/EGT one but the EGT is ruled out by the weight of the sender probes - pity). I have a Tiny Tach which is a 'brute' at 85 g but at least that includes the sender - no more than an induction wire wrapped around the HT lead!
Stuart, I have the usual VDO type stuff and its typically around 80 to 100g for a 2" instrument. The VDO pressure sender is 120g so I now realise that rules out a cockpit oil pressure display. But the temperature sender is quite light by comparison. I do like as much engine instrumenetation as possible as it helps avoid potentially expensive engine hassle but the weight restriction is so tight that I am being forced to a meagre level of instrumentation.

[Brian Hope]

Hi Richard, when my Jodel left the factory (in 1957) it had an oil pressure light and a rev counter for engine instruments, nothing else. Makes you wonder whether some of today's pilots would ever have contemplated leaving the ground in it, what with their penchant for megga-bucks screens and gizmos that do everything but make the tea.

[Richard Mole]

Hi Brian, an oil pressure warning light may well be on the cards for me too. I agree that the law of diminishing returns kicks in. On the first few flights of a new type with an (almost) new engine type, I would expect that most of one's attention will be on the handling of the aircraft with just enough notice of the engine instruments for warning against possible loss of engine power (thats not going to be so much to lose in my case!) or worse. That argues for the bare minimum of well presented engine info. A warning light gets high marks in that scenario. But it is the early operation of the engine where one can avaid damage from over-heating & the like if the installation such as cooling is not up to snuff . That argues for as much engine info as possible - shame there is unlikely to be the pilot attention to absorb it! Hopefully, I'll find a middle path.

Its not that I am anywhere near contemplating actual flight at this stage - rather I am doing a final final projection on total weight, and cg location and range.

Richard

[Bill McCarthy]

Maybe its just me but I have never got on with digital readout information. Even the digital watch, which seems to have gone out of fashion took that fraction of extra time to convert to what it would be on a conventional watch face. It would be the same with me trying to get used to the "grasshopper" vertical readout with little dots moving up and down rather than the good old needle hand flailing about.

[Rod1]

Richard

Would you save weight by going for a single glass screen to do everything? I think this is allowed in a micro.

Rod1

[Richard Mole]

Bill, I totally agree as far as flight instruments are concerned - give me a standard ASI and altimeter etc any day. But what about the familiar analogue fuel gauge - I'd prefer that info digitally presented and if the grid is every 5% of total fuel (say) then you are presented with a nice steady display that only changes as each 5% of fuel is consumed.

For engine monitoring there are pros and cons of analogue and digital. You can integrate your reading of a standard oil pressure gauge with your scan and hardly know that you are doing it, because it is so effortless. But if you want to know how oil pressure actually varies with oil temperature and OAT then give me digital presentations every time.

Rod, I personally wont be kicking the standard flight instruments into the long grass any time soon. Perhaps I'm too old to change but when multiple difficulties occur such as partial electrical failure, poor ambient lighting, glasses temporarily mislaid, heavy pilot workload, disorienting inputs when the horizon goes awol etc etc I am absolutely sure that I prefer the standrad 'steam driven' instruments. That said, I do prefer the digital presentation of most engine parameters as they are more useful for engineering purposes.

[Bill McCarthy]

Richard, Like you, I would want my flight instruments such as ASI and Altimeter to be classed as "essential" instrumentation in hard wired analogue, whilst non essentials like engine information, fuel etc could be grouped together in digital format.

[Ian Melville]

Richard, If you are trying to beat a empty weight target (eg 115kg for SSDR) then why don't you just make the instrument/s plug in for flight testing only, hence excluded from empty weight. Then just a couple of warning LED when set parameter exceeded in flight.

[Rod1]

A modern digital system like an Enigma will display any parameter any way you want. You want a conventional ASI, no problem you will get a perfect reproduction of an ASI, without the instrument lag of the original! For engine info you can have bar graph displays with the actual value displayed underneath, or a representation of a conventional oil pressure gauge etc etc. With a bit of thought you can build in a lot of redundancy and I suspect you can save a lot of weight, particularly if you want a horizon and T & S, together with full engine info, full flight info and GPS all in one unit. By using the “conventional” instrument display on the screen there would be no transition issues at high workload, and you could move onto a more modern display gradually.

Rod1

[Richard Mole]

Ian, that's a good idea - however the weight ofthe senders is often quite considerable and it may not be as practicable to install them just for flight test work as it would to plug in instrumentation provided that the senders were peranently installed. But I agree it does reduce the weight.

Rod, can you please tell me the weight of the screens?

[Rod1]

It would need more work but I think this would replace all the other instruments;

Stratomaster Ultra Weight: 980 grams.

Rod