A Close Shave

[PilotOnline]

Yesterday I was on my way back from Turweston heading down towards BNN at around 2400ft in a PA28. Approximately abeam with WCO I spotted a C152 (I'm pretty sure it was a 152 and not a 172) descending toward me in a controlled shallow turn in my 11 O' clock position on a constant bearing to me. At this point I thought, ok, enough separation exists for me to turn away and avoid the possibility of a collision which I promptly did. I increased to full power, banked to the right and the Cessna passed probably no more than 80-100ft across my tail. I have seen other aircraft come close before but what amazes and concerns me is that at no point did the other aircraft appear to notice me, even from 200ft away. Has this sort of thing happened to anyone else? Am I just being a bit paranoid because that was my first experience of a close call?

[Keef]

Were you obscured from his view by his wing? Does happen with 152s, I know.

Did you get his registration? An Airprox report might sort something out. If you felt there was risk of collision, you should do one...

[PilotOnline]

Keef,

Initially He was flying straight towards me but I could still see straight into his cockpit as I started to turn. However I have never flown in a 152 so don't know how limiting the visibility can be in a turn. Unfortunately due to the necessity for me to turn away I couldn't see the registration of his a/c.

[IO540]

I've had a head-on situation, with me turning right and with the other pilot turning to his LEFT... I think that's probably worse than not seeing another plane.

Cessnas have terrible visibility when turning; having spent 60 hours in them I would never fly one now.

[Fly Stimulator]

I haven't had as close a call as that, but I am rather paranoid about other aircraft anywhere near London VORs, especially since GPS now ensures that everybody passes directly over the top of them.

I've been doing most of my flying recently in an aircraft fitted with a Skywatch TCAS system, and it's alarming how many aircraft it alerts me to that I'd simply not been aware of. Even with three or four people looking out it can be impossible to spot another aircraft in spite of knowing it's there and where to look. It's rather sobering, but has its own dangers in that TCAS can lull you into a false sense of security if you forget that there are plenty of aircraft out there without transponders, and a surprising number with transponders either not working or turned off.

This is one area where a healthy dose of paranoia is a good thing

[stillin1]

For what it's worth:
IMHO taking a radar service - LARS, RIS, FIS or what ever you can get prolongs a long active and healthy life. There IS a s@@t-load of stuff out there you never see no matter how good yer lookout scan is

[Aussie Andy]

I live within about 2NM of the BNN VOR, south west of the beacon in Chesham. While sitting in the backyard yesterday (with friends, nice BBQ, lovely blue skies) I noticed that there was quite a high number of both GA aircraft (mostly PA28, C172 and similar) as well as, more unusually I suppose, quite a lot of microlights (was there a rally somewhere?). For a while there, mid-afternoon and early evening, I reckon there must have been about two aircraft passing within earshot about every 10 minutes.

I suppose therefore that there is a markedly risk of higher on blue-sky Saturdays and Sundays like this anywhere near the beacon, and generally at high-traffic "pinch points" such as this around the LTMA where large numbers of aircraft OCA must route within a confined space below the 2,500' altitude lower-limit and the generally 500~1000' terrain.

Be careful out there - especially on "nice" days!

Andy :O

p.s. stillin1: it can be difficult to get a radar service in these conditions, for a couple of reasons:

1) not within usual service area of Brize, Farnborough etc.
2) Luton don't do LARS in my experience
3) On sunny Sundays like this, Brize etc. quickly reach saturation and can't provide a service anyway.

[bluskis]

In a couple of threads on GPS there were pilots who advocated that they led to lack of lookout, and were therefore dangeous.

While lookout is one of the most important anticollision devices in VFR, there were studies reported relatively recently which showed how limited is the effectiveness of lookout.

Hence the advisability of getting a radar service if you can, chosing an odd height, preferably not the one I have chosen, being hyper cautious near VORs around London, and while tracking between, and chosing the best Frequency to talk to if no radar is available.

Tempting fate, it is fortunately very rare that a collision actually occours, and I think most of those are in or near circuits.

[flower]

Just for the record folks a RIS means you are still responsible for your own seperation from aircraft, we will do our best to tell you of traffic but you must still lookout.
If flying on a FIS we will only tell you about other known traffic also receiving a service from us .
However yes you are more likely to be informed of other traffic be it in generic form ie:
several contacts observed in the vicinity of etc ....

To traffic in your 3 oclock range 5 miles etc....

If receiving a service from ATC

[M14P]

If you are worried about 'too accurate' GPS navigation leading to arriving overhead a VOR along with someone else consider the following.

1. Navigate to waypoints other than VORs because that is what GPS is all about (Intersections can be useful or perhaps some of your very own USERS)

2. Fly deliberately 1 NM right of track and 100' high or low on your usual altitude. (That's what we do on African airways!)

3. Brief all of your passengers about mantaining a lookout and how to determine conflict (relative bearing etc) as well as how to describe intruders position

4. Use all available lights when you consider yourself in a high traffic area

5. Buy and fit some 'CometFlash' strobes

m

[niknak]

Hi tech gadetry with all the whizz bangs and bells is all very well, but a lot of these posts seem to be straying from the basic principle of VFR flight, see and be seen.
If youve got your head down looking at gadgets, you aren't concentrating on what you should be doing, and having one lookout is all very well, but two or three is potentially flying by committee.
Take advantage of any service from a rdar unit, even with a FIS we will endeavour to give you as much radar derived traffic information as we can, but when flying in such busy airspace we can only do as much as the traffic levels permit, the rest is up to you.

[witchdoctor]

The Westcott NDB gets paticularly busy as many of the aircraft from the large schools at nearby Oxford and Cranfield use it for IFR training at lowish (i.e non airways) levels in addition to VFR general handling. I've used it many times during my training and my instructor always referred to it as Tin Alley and was paranoid about lookout in that area. Add in all the regular GA stuff and it gets very crowded in a small area of uncontrolled airspace.

Other NDBs/VORs (away from controlled airspace) can be a lot quieter, but unless you have good local knowledge you won't know until you're in the thick of the action.

[FWA NATCA]

As a controller it is shocking seeing how often VFR aircraft primaries (radar return) pass each other, often at the same altitude indicated on their mode C. I can't count how many times I've issued traffic to VFR pilots receiving radar advisories only to have to issue a traffic alert because neither pilot saw the each other.

As for M14P's suggestion to fly 100 ft higher or lower there is an danger in that idea too. An aircraft's mode C can be off by 300 ft and still be considered within tolerance.

Now here you are flying along enjoying yourself, at what you think is 4600 feet, but your altimeter is off by 200 feet so you are really at 4800 feet. The other acft is supposed to be at 5000 feet (assume he is IFR) but his altimeter is off by -200 feet so he is really at 4800 feet too. Radar issues traffic to you, "traffic 12 o clock 5 miles C172 at 5000" the other pilot is issued "traffic 12 o clock 5 miles PA28 at 4500", both of you think hey, we're ok, we are seperated by at least 500 feet and it's a big sky out here, so neither of you bother to look for each other.

You both merge at 4800 ft, and hit.

I had a private pilot visiting me in the radar room one day who use to do the 100 or 200 feet higher thing. As he was sitting next to me as I was working radar he listened as I issued traffic to two airplanes, as their targets merged one of the pilots said, "holy ****, that was closer than 500 feet. I said your mode C shows you at 6000 and the other acft at 5500. The other pilot said well I usually set my altimeter so that I fly alittle higher than normal so that I don't run into someone else.

Mike
NATCA FWA

[PilotOnline]

Thanks for all the replies. I have to say the only reason I tend to use BNN is to make sure I don't fly into Luton's airspace i.e keeping to one side of a specific radial and I use it as an entry point to Denhams circuit whe they're nusing runway 24. I know the Westcott NDB area is a minefield, despite the fact that it is an NDB station it is a great VRP but I try not to fly over it. When the event in question happened I was flying a considerable distance from the WCO NDB and still north of Halton.

[Aussie Andy]

FWA NATCAThe other pilot said well I usually set my altimeter so that I fly alittle higher than normal so that I don't run into someone else. Correct me if I am wrong, but I don't believe that pilot changes to altimeter pressure settings have an effect on transponder mode C encoding, which I had thought is fixed to standard (i.e. 1013.2 hPa)

Andy

[BEXIL160]

Andy...

You are quite right... BUT, the ATC equipment will convert the Mode C to an ALTITUDE (if you are at or below the Transition Alt)

Which means that a/c one at 4800ft may be indicating 4600ft on radar (within the allowable tollerances) and a/c two is indicating 5000ft, but actually at 4800 as well... clang.

Bear in mind that in the USA the transition alt is somewhat higher than over most of the UK..... which is another argu... no, no, no I meant Thread.

rgds BEX:cool:

[Aussie Andy]

G'day BEXIL - I understand... but regardless of transition levels and your display settings, I still don't think that the pressure setting within the aircraft will alter your display.

When VFR, I believe people should fly quadrantal/semi-circular levels (as appropriate according to jurisdiction), maintain a good lookout(!), and where possible get extra information / separation if available from ATC services. The only way to do better is to remain IFR within controlled airspace!

[FWA NATCA]

Aussie Andy,

I've flown as aircrew (back in the 70's) and until 9/11 took FAM's whenever the opportunity presented itself, so I know how hard it is to see other aircraft. It still surprises me that the majority of all mid airs occur in VFR conditions, often in clear and unlimited visibility.

As others have said NDB's and VOR's act as magnets and traffic over or near these fixes can be quite heavy and pilots need to be extremely watchful for the other guy.

As for transition altitude if you are refering to when Flight Levels begin and pilots put 29.92 in their altimeter, this doesn't occur until FL180 in the US.

Mike

[bluskis]

The quadrantal rule is not much good under the London TMA.

You realistically only have 900 safe feet to chose altitudes from, and in turbulent conditions you dont want to be using the last 300 ft of those.

In this area a radar service is desperately needed for GA. By that I mean one that will always be there, and as I have said in other threads, I fully appreciate the service Heathrow and Thames do give when they can.

[FlyingForFun]

Good point about altimeter errors.

But don't pilots check their altimeters before flight? I don't know about anyone else, but when I set the QNH, I check that the altimeter is reading the aerodrome elevation, or slightly lower. I'd like to think that if my altimeter was out by 100', I'd notice, and get it fixed, legal or not.

FFF
----------

PS - Is there now an argument for flying around at exactly 3000', since everyone else seems to be adding or subtracting a couple of hundred feet from the round numbers? ;)

[Aussie Andy]

FFF: Snap! Was thinking this, will give it a try ;)

[englishal]

Its all very well to say VFR flight is "see and be seen" BUT its the time you DONT see the other aircraft that is the problem. I have come close 3 times as far as I remember, first was on my solo X/C, flying along scanning the sky and suddenly this old war bird flew past, opposite direction about 200m off to starboard same altitude. I hope he saw me becasue I didn't see him even thought I was being incredibly vigilant [was in a radar shadow as well which didn't help]. Second time was rejoining at Long Beach, another aircraft was joining as well, the controller was screaming at me the traffic info, I couldn't see it at all. The controller was screaming at the other aircraft, and he couldn't see me. In the end the controller gave me vectors and the other aircraft appeared out of a blind spot less than 100m away, and I guess we appeared out of his blind spot. Third time was climbing out of Long Beach again, just departed and picking up VFR flight following, and was issued a traffic alert, traffic less than 0.25 mile, same altitude coming straight for us. We took avoiding action by decending rapidly [he should have turned right] as we didn't feel it safe to turn. The scary thing was that in avoiding this aircraft we flew through the wake of another unseen aircraft which must have been in that spot less than a few minutes before.

In all these experiences we were flying VFR, scanning the sky and not playing with gadgets in the cockpit. These other aircraft just weren't seen, not through lack of trying. Maybe all GA aircraft should be painted a high vis colour or something, or tow a banner with a big arrow pointing towards the aircraft :D

The scary thing is that in the UK you are perfectly allowed to fly around in cloud [with IMC rating] with no form of radar service at all, and no flight plan,.....sends shivers down my spine ! In fact Radar services are 'discouraged' by a lot of people I've talked to, especially in good weather. I would not dream of flying in the LA Basin without a radar service even in good weather, you would have to be mad or suicidal in my opinion.

Rgds
EA

[FWA NATCA]

englishal,

A friend of mine had his Cessna 180 painted day glow yellow with a blue strip because of a near miss that scared the you know what out of him.

I can't believe that some pilots would encourage others to avoid using VFR Radar flight following, maybe they are working on being bold pilots. We are sitting in front of that scope to provide a service, and VFR advisories (when traffic permits) are part of our job.

Safety is a team effort and controllers are valuable part of that team.

Mike
NATCA FWA

[Aussie Andy]

I can't believe that some pilots would encourage others to avoid using VFR Radar flight following Who said that?

[englishal]

Not VFR flight follwing in the states, but a RIS in the UK. Every time I've gone up with an instructor and suggested getting a RIS [radar information service] I've been told to get a FIS [flight information service for those who don't know......next to useless in my opinion unless you want to know the altimeter setting]......"thery're too busy"...."they won't give us one anyway"......"we're VFR and responsible for our own seperation"...."they're miserable b**tards"...etc....[probably opened a can of worms here :D]. Ca't fault the US system though, best in the world.

I think Black is meant to be a good colour for 'high' visibility in the air for some reason [unless at night I suppose], I remember reading that Red cars are involved in the most accidents or something...

Right enough drunk ppruning, I'm trying to give it up :D

Cheers
EA:D

[AlanM]

....."thery're too busy"...."they won't give us one anyway"......"we're VFR and responsible for our own seperation"...."they're miserable b**tards"

too true!!

As much as we try to help on 132.7/119.9 we are not a LARS unit and as such are not staffed to provide Radar services outside CAS.

Your instructor speaks many a wise word. Esp the miserable b**tards bit!

Seriously, we don't have time to give a service most of the time. When the vis is 30km+ do you really need one?

It isn't really helped by aircraft calling for a service when routeing Elstree to Southend via LAM and the vis is 30km+.

Have I missed something but what is wrong with the see and be seen principal of VFR flight?

[englishal]

Knew I shouldn't have drunk all that red wine last night :hmm:

what is wrong with the see and be seen principal of VFR flight

Nothing in theory, but sometimes especially in busy airspace you just DONT see all the traffic, not through lack of trying.

I'm sure you're not "miserable b**tards" at all, I think he was just generalizing that sometimes its not even worth asking as you know the respone you'll get [especially from certain facilities:D].

Cheers
EA:D