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P-51 versus Malibu M600

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Old 6th Jan 2023, 13:45
  #41 (permalink)  
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If the reflector gunsight screen is fitted and doing nothing useful, perhaps the image could be projected on to it?
Sure, excellent idea, but with which complexity and costs to get that done ? Mixing 1945 and 2020 technologies is not that easy .
​​​​​​​If it were me, I would want any help I could get to see hidden aircraft
Sure again , but a far cheaper and simplier anticollsion system that a caera / HUD would be if both aircrfaft had been fitted with a traffic alert , like a FLARM that we all in Europe in the gilder community.for instance Unfortunately not working above 250 Kts.,so not made for high peformance aircraft. ..
But again , in a flying display , especially y during a high speed , low level trajectory , trying to catch another aircraft ( the P-51s) and stay within the display line , you are only looking outside , not to a screen , unless it beeps in the heaset ( which the FLARM does)
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Old 7th Jan 2023, 00:36
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Just an aside on FLARM. I’ve flown four towplanes and five gliders with FLARM.

It is not the universal panacea. Its functionality is highly dependent on antenna type and installation. When it works well it’s great but it’s not a substitute for a good lookout.
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Old 7th Jan 2023, 00:43
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Not having used FLARM, would it be useful when flying in formation or would it just be going off all the time?
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Old 7th Jan 2023, 02:11
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abgd,

I’ve not flown formation with FLARM so I don’t know, but the algorithms are surprisingly sophisticated. It is not just a proximity sensor.

Each unit broadcasts not only location and altitude, but also track, groundspeed, altitude change rate and current turn information. The receiving unit uses this information to predict the track of each aircraft and determine if a collision risk exists.

For example, if circling with a glider at the same altitude but on opposite sides of the thermal, there won’t be any alarm.

If approaching an opposite direction, co-altitude glider on a ridge, you will hear a warning followed by a collision alarm, until the other glider is in your 10 o’clock or so, at which point the algorithm determines you are passing each other and decides there is no more collision risk.
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Old 7th Jan 2023, 08:51
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Originally Posted by India Four Two
Just an aside on FLARM.
It is not the universal panacea. Its functionality is highly dependent on antenna type and installation. When it works well it’s great but it’s not a substitute for a good lookout.
We can all agree on that , FLARM is just an addtional tool , it is not a TCAS, , but for the sake of the discussion here , in this accident here FLARM could have maybe helped. as FLARM unlike TCAS works on the ground,. , but for instance it would have definitively work with the collsion in the airshow in the other thread (but as long as the P-63 stayed below 250 Kts)

I have my own aircaft equipped with Power FLARM ( detecting both FLARM and Mode S transponders aircraft) since the start in 2012, so over 10 yaers ago , and all the gliders I fly in my clubs are equipped. I recently upgraded mine with a LX traffic info display , shich looks similar to TCAS display ( distance, azimuth and arrows with vertical distance ) and most impotantly it beeps in your headset when a conflicting traffic is very close. to attarct your attention. with 3 antennas it works extremely well. and saved me on a couple of occasions in around 2000 h flown with it .
@ afgd :
would it be useful when flying in formation or would it just be going off all the time?
No you can tow gliders and fly in formations if will not trigger , it will just let you know the traffic is there , it will only trigger if another FLARM equiped aircraft is in an imminent conflicting collision course, . If , like in my case ,you have your aircraft equipped with both FLARM and a mode S transponder , to avoid self detection you just enter in the FLARM menu the icao hexadecimal code of your transponder . The system is quite good now..

Last edited by ATC Watcher; 7th Jan 2023 at 09:17. Reason: addition
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Old 7th Jan 2023, 14:49
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Originally Posted by ATC Watcher
....
No you can tow gliders and fly in formations if will not trigger , it will just let you know the traffic is there , it will only trigger if another FLARM equiped aircraft is in an imminent conflicting collision course,......
Yep, triggering "only" on potential collisions, though how to find out the potential collision target after the warning, as well, how the software will be able to "predict" an imminent collision, in a situation with varying/circling trajectories (in 3D with highly varying speeds as well) ? Not to say, how to discriminate out all the false-alarms ?
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Old 7th Jan 2023, 15:57
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how to discriminate out all the false-alarms ?
That wwas true on the very first versions with the leds, basically it told you there is somebody conflicting out there , look ouside and change course, and in case multipme targets, it also only warned you of the closest one . .The new Power Flarm dispays like the one which I added now, is discriminatoty , you can choose a typical TCAS-like display, and the alert mode ( white baground with red area to avoid ) . see here : https://www.lxnavigation.com/gliding...raffic-square/

how the software will be able to "predict" an imminent collision, in a situation with varying/circling trajectories
I have no idea, just using it and , again, it works quite well. One major fact not to forget though , it only works if the other target is also FLARM equipped, or in case of Power Flarm , has a Mode S transponder and puts it on..Mandatory I know, but we all know it not always the case in practice.. ULs are a big issue in that respect.
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Old 7th Jan 2023, 16:53
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Not to belabor the obvious to the tailwheel pilots on this thread, but S turns and eyes out on taxi always works. Things happen really slow on the ground.

Disclosure: I have no P51 time. But, I can't see forward on any tailwheel aircraft that I fly.
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Old 8th Jan 2023, 10:02
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Originally Posted by treadigraph
(Edit: In the past Discorde has very kindly provide links to some of the late Neil Williams' articles from Shell Aviation News - herewith his tale of operating a Spitfire from Bex! )
Neil Williams is a classic example of how a very experienced, well respected and loved pilot can succumb to human error.
Doesn't matter how many cameras, warnings or gizmos you include human error will still creep in.
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Old 8th Jan 2023, 10:16
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Originally Posted by Jhieminga
See here for a Dutch language page with several photos and some bits of accident report (in English): Ongevallen/incidenten 1978
Thank you!

Saw a video snippet of a J-3 Cub chewing its way up the wing of a C152 a few days ago - not sure when the prang was. I'd have thought the view ahead from a Cub on the ground wasn't that bad, though I've only ever been in the back of a J-3 floatplane! If you can't see weave.
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Old 8th Jan 2023, 12:06
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Originally Posted by ATC Watcher
That wwas true on the very first versions with the leds, basically it told you there is somebody conflicting out there , look ouside and change course, and in case multipme targets, it also only warned you of the closest one . .The new Power Flarm dispays like the one which I added now, is discriminatoty , you can choose a typical TCAS-like display, and the alert mode ( white baground with red area to avoid ) . see here : https://www.lxnavigation.com/gliding...raffic-square/
Yep, the original versions were pretty lame though things improved.

Originally Posted by ATC Watcher
I have no idea, just using it and , again, it works quite well. One major fact not to forget though , it only works if the other target is also FLARM equipped, or in case of Power Flarm , has a Mode S transponder and puts it on..Mandatory I know, but we all know it not always the case in practice.. ULs are a big issue in that respect.
While your description is interesting, it doesn't give an answer to the core question: Will the FLARM be able to cope with a non-standard situation like an air display ?

The false-alarm avoidance algorithms will likely be based on "normal" flying behavior, IE, a predictable flying behavior of all detected airplanes as well a "normal" behavior of "myself". Deviate from that and the algorithms go haywire and false-alarms do become the norm.

Add to that, that, as I wrote before, my estimate is, the P-63 pilot was probably behind the aircraft, with the consequences that alarms (from whatever source, including the airboss) will likely be ignored as being mentally "irrelevant". An aspect that repeatedly shows up in discussions about "behind the aircraft" circumstances.

Not to say, following your link, I do have my doubts, whether a display like the one in your link, will provide sufficient dynamic 4D insight (at a glance) into a developing situation like the one for the P-63, from the top of the climb towards the accident location. If the P-63 pilot would be given a warning, I do expect it to be discarded as a false alarm, since it would be the intention of the approach figure to get close to the B-21, and it can be expected in some moments of time, there will be conflicts detected.

Not to say, we should realize, the factual collision was programmed only shortly before the accident, when the P-63 started a heavily banked turn. Or so to say, without this banked turn of the P-63, there would not have been a collision between the P-63 and B-21, effectively reducing the time between establishing the collision course (with a potential FLARM alarm) and the collision to be only a few seconds.

(Without the banking/turn, there would have been a severe overshoot of the display line, towards the public, though).

Not to say, there would have been already several nuisance alarms, while the P-63 was climbing to the top of the approach figure, due to its prox with the P-51.
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Old 8th Jan 2023, 12:52
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Originally Posted by treadigraph
Thank you!

I'd have thought the view ahead from a Cub on the ground wasn't that bad, though I've only ever been in the back of a J-3 floatplane! If you can't see weave.
Or tack!
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Old 8th Jan 2023, 13:14
  #53 (permalink)  
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Originally Posted by DuncanDoenitz
Or tack!
Aye aye!
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Old 8th Jan 2023, 15:20
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Ready About? Comin' About! A commendation to treadigraph for the link to those superb Neil Williams stories!

- Ed
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Old 8th Jan 2023, 16:27
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@ WideScreen
While your description is interesting, it doesn't give an answer to the core question: Will the FLARM be able to cope with a non-standard situation like an air display ?
Frankly I do not know,,but , like you, I would think it is not , if we are talking multi aircrfat types simultaneous displays like in Oshkosh. FLARM has been designed initially for gliders ( anti-collision) and helicopters ( cables avoidance , especially in mountains) not for air displays.

That said, the system today gives little false alarms. For instance in a glider if I am in a thermal with 3 or 4 others in very close proximity , once we spiral ( same way) and keep our distances with one another ( something as low as 2-300 ft laterally ) no alram, however if one is catching up on another one ,both will get an alarm . So the system is quite sophisticated. but I do not think it is not made to react for fast , abrup maoneuvers .So it is not so much the false alrams that I think would be the problem but rather the non-detection of the geometry on some targets

This is why I said initially that a system like a FLARM system could help., but not really the exact current FLARM system .
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Old 8th Jan 2023, 16:49
  #56 (permalink)  
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Hello Posters,

The P51 vs Malibu and P63 at Dallas are both worthy topics of discussion. Could we keep each in it's own topic please, just so the discussion does not get confusing?

My taildragger has the best forward visibility of any fixed wing I have flown - 'cause the engine and prop are behind me! But, yes, when I have taxied the Stearman and Harvard, weaving is the only way you're going to see safely in front.

Thanks, Pilot DAR
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Old 8th Jan 2023, 16:49
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Originally Posted by treadigraph
I'd have thought the view ahead from a Cub on the ground wasn't that bad, though I've only ever been in the back of a J-3 floatplane!
A J3 floatplane is in a pretty level attitude. A J3 in the 3 point attitude is not. You don't have forward visibility.

When I was a primary student in a PA12, I had a buddy who was doing his tailwheel training in the same aircraft. He was really tall and I'm not. He insisted to the instructor that he could see forward without weaving. This was true to a point, however one day he missed the end of the taxiway and took out a light. There is always going to be a blind spot in front of you but no problem seeing a little to either side.
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Old 8th Jan 2023, 17:44
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Dinky FLARM displays are just barely adequate in gliders, but panel space is limited.

Traffic View is available in 80mm and is becoming popular in tow planes.

FLARM traffic can also be displayed on glider flight computers which are really handy for strategising. I pick up ADS-B 1080 traffic several miles away and can arrange to stay well clear if I can't make contact on radio.
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Old 8th Jan 2023, 20:05
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There were (probably )3 people who hold some responsibility for the accident/incident....think of it as an RTC...answers on a postcard..
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