Radar Detecting Other Aircraft

[Clockwork Mouse]

This may appear to be a facile question to them in the know, but here goes anyway.
I've just read about the Airprox last year in Scotland when a Tornado on the approach narrowly missed two Swedish aircraft which passed in front of it at a distance of about 200 metres. It reminded me of something I have often wondered about.
Such incidents are not uncommon. As aircraft such as the Tornado have a powerful radar in the nose and a bloke in the back looking at it, can someone in the know please explain to an ignorant Pongo why such incidents occur. I assume the radar is not switched off to save electricity, but is it in a different mode which means it can't detect nearby aircraft, or is the screen being used for a non-radar display, or what?

[BOAC]

Nav at that stage would be finishing sharpening his pencils and putting them away, so radar not watched, whereas a Lightning Pilot, ever attentive and watchful.............................................

[Pontius Navigator]

The nav was possibly using the radar to monitor the approach or was monitoring the approach.

The other aircraft may be been on vectors outside the radar cone etc etc

[mugwuffin]

simple answer? the gr4 radar is an air to ground system not an air to air system. altho in the right hands with the right conditions it performs adequately v other aircraft it's not optimised for it. and, as mentioned above, there may well be a whole host of more important things for the nav to be doing, from monitoring the junior pilot's ever increasing alpha to ignoring his hore****e emergency brief.

[Timelord]

The GR4 was in the visual circuit. That means that they were protecting themselves from other aircraft purely by looking out, and that, presumably is what they were doing. The aircraft that they came into conflict with was on an instrument approach. It was the job of the crew in the visual pattern to avoid the crew flying on instruments (and therefore not looking out)

The problem was that the weather was not really fit for the visual circuit, so that crew could not see the aircraft on the instrument approach.

Why an aircraft was in the visual circuit when the weather was not fit is the crux of this airprox.

Neither crew would have been using the radar in an anti collision mode as they both had more important things to do at that stage.

[ian176]

Neither crew would have been using the radar in an anti collision mode as they both had more important things to do at that stage.

The pilot always has something more important to do since the only radar display he has is for the TFR :)

[Timelord]

Neither of the crews!

[whowhenwhy]

Timelord is close enough although the ac were the other way around with the Swede's in the "visual" circuit and the radar was indeed being used to monitor the approach.

[Willard Whyte]

whereas a Lightning Pilot, ever attentive and watchful.............................................

Lightning on an approach?

Out of gas, out of options...

[airpolice]

And out of weapons, having fired both shots, he would be restricted to taking cheap shots at modern day multi crew "fighter" aircraft.

[Clockwork Mouse]

Thanks for your comments on that particular incident.
I am still not clear about the use of the aircraft's radar while, for example, flying about in the LL system. There have been many instances of near misses with civilian light aircraft, and I have personally been scared sh*tless by an F4 many years ago and have no idea whether he actually never saw me or was deliberately putting the wind up a pongo. Perhaps it was you Beagle?!?
I have always assumed that the crew have a continuous radar picture in the cockpit of what lies ahead and on either side of them, both terrain and airborne objects, as they blat about, in addition to the pilot's eyeballs.
Am I wrong?
And what is a TFR?

[Willard Whyte]

Terrain Following Radar

[davejb]

There's a basic misunderstanding here - an aircraft radar fited to an interceptor will be designed for air to air and therefore would allow the crew to spot conflicting aircraft. However, a GR4 is not an air to air beastie, and it's radar is designed to be good at spotting the ground, buildings, wandering Lightning pilots, and so forth.

It's a misconception, generally, to imagine that a radar can look at the ground and the air at the same time, although some radars (such as that fitted to the Nimrod...knew we'd get another Nimrod thread going eventually <g>) had the ability to swap between modes of operation so that one could swap between air and ground search (note - not cover both at the same time).

Dave

[ghostnav]

and even if you are in an AD nav, you do not spend 100% of your time looking at the radar! Lookout, other instruments, height checks, fuel checks, Warning Panel, lookout, as well as the radar! On approach, the radar is rarely used if under the control of ATC and the mode used then is unlikely to be air to air.

[Ivan Rogov]

Most of it has been said, the main reasons are (there are many more)

- Not all airborne radars are the same. AEW, AI, TFR, GMR, Wx, SAR, Nav, FC, Maritime, etc. Even if they are the same type, different models and versions of those models can have very different capabilities or performance.
- Type of sortie/mission. Generally at LL the aircraft crew will spend much less time looking at the radar in an Air to Air mode for various reasons (if they look at the radar at all!).
- Scan limits. Some radars are 360 deg, most have some form of sector and an update rate i.e: Scans 90 deg on the nose, one sweep every 1/4 second. One radar may be in a different scan type depending on the mode it is in.
- Serviceability. Even if an aircraft has the right radar to see you, it might not be working. Some aircraft will get airborne with an unservicealbe radar if the sortie does not require it and there is no spare part/aircraft/time.

Of course the latest AESA radars might have a bit more flexibility is some areas. However radar (even the latest types) is not the best way to avoid other aircraft especially at LL.
Some will tell you that a good look out is the answer, but this is not true due to human performance factors. TCAS is by far the most effective way of avoiding other aircraft and should be fitted to all aircraft, especially Military ones.............mmmmmmmmmmm I wonder if it is?

[Clockwork Mouse]

Thank you all! I am now much better informed.

[The Old Fat One]

One more thing...

Some airborne contacts can be detected in a ground/surface search mode if they are moving slowly enough and are close to the ground.

The S/W would detect helo's pretty much in any mode of operation; puddle jumpers (that's Cessna's in pongo lingo) too.

Thus a helo in the hover (or moving very slowly) might well spotted, but equally could be mistaken as a something on the ground/sea.

I echo IR comments...

There are proper ways to avoid other aircraft...from VFR mark one eyeball, to ATC, to fancy propose built electronic gadgets for collison avoidance. On board radars designed for other purposes are IMHO well down the list.

[Clockwork Mouse]

Fascinating! Clearly a very great deal more to it than I believed. Thank you.

[Justanopinion]

It's a misconception, generally, to imagine that a radar can look at the ground and the air at the same time, although some radars (such as that fitted to the Nimrod...knew we'd get another Nimrod thread going eventually <g>) had the ability to swap between modes of operation so that one could swap between air and ground search (note - not cover both at the same time).

Just as a point, the AESA radar can look at Air to Air and Air to Ground at the same time. Not that this changes the fact that looking out the window is always going to be better at low level.

[Brian 48nav]

Following on from my friend BOAC's input, a Transport Nav would stay ever attentive and watchful until safely in the crew bus after landing, but still keeping an eye on the driver. In my case this watchfulness remained until I had seen the colour of the captain's money and he had placed a cool beer in my hand!

I would not dream of sharpening my pencil or using my rubber until safely home with the lovely Mrs B48nav.

Taking off my 'nav union' hat, my off-spring 'Jag Mate' told me that Tornado mud movers were the easiest to 'bounce', as the backseater was always busy playing computer games.

B48N,

PS BOAC, we were at a tea party with the usual suspects yesterday and it wasn't until after it was over that Ron told me his neighbour, a Grp Capt Tornado 'nav' (!!??) was there. I missed out so much fun!

[Pontius Navigator]

I would not dream of sharpening my pencil or using my rubber until safely home with the lovely Mrs B48nav.

Careful Brian. Our cousins may read something entirely different to you innocent statement.

[BOAC]

Indeed, Pontious - his para 1 reflects all the skill, craft, experience and cunning that I know of him. His para 2 leaves me breathless with the innuendo. I will look at Mrs B48 in a new light:)

Brian - what a missed opportunity (the tea party!). Our 'mutuals' would, of course, been totally shocked by the game you wish you could have played.