Mid-air Collisions

[Wander00]

A comment elsewhere about the Pinner, or Northwood (depends which report you read) collision in 1948 between an RAF York and a SAS DC-6 led me to a search on Wikipedia, and I was astonished by the number of mid-airs between military aircraft, especially through to the 70s and 80s. Indeed the Northwood accident is claimed to be the last mid-air involving a civilian airliner in the UK. Anybody else looked at this aspect of aviation history. I found a long article about the Norhwood accident in a paper written for the local history society. I was surprised that I have no recollection of the accident itself, nor my parents discussing it, and we lived only about 4 or 5 miles from the crash site.

[Mike6567]

Collision over Copsewood (Northwood) 1948.
I flew with someone who remembered the location of the crash as a youngster in the 1950s. I then looked for it in the early 90s while walking the dog but was unable to find anything. I think I checked with the local history for information but no success. My family lived in Ickenham at the time of the accident but I never heard it discussed.
Mike

[Wander00]

Mike - I will find the link and post it - map shows where the parts of the two aircraft fell


w

[Wander00]

Flight article - https://www.flightglobal.com/pdfarchive/view/1948/1948%20-%201020.html


Local History article - http://btckstorage.blob.core.windows.net/site8867/Journals/2008/J08%20Pg7-15.pdf


Seems in some places called the Northolt Disaster. Also seems there was a shortish thread on this topic in......2004!

[wiggy]

I was astonished by the number of mid-airs between military aircraft, especially through to the 70s and 80s.

Can't comment on civvie vs. Mil but mil on mil collisions sadly went with the territory and the time (Big air force compared with today, aircraft more basic, cold war tactics). Anyone who lived through that period will tell tales of the "F**** me that was close" moments or worse still tell tales of not realising you'd only just missed someone else until the debrief.

Why?

Firstly much more military aircraft around in the UK than there are now, all operating without any form of electronic collision avoidance. ( Look at the number of fast jet squadrons based in the UK now and compare with the number, say in 1980..)

Lots of formation flying ( not just the Reds, operationally as well, just about every sortie..shouldn't happen but there's always an increased risk of a clunk there)

Often as not operating (especially during training) in busy "open" airspace using "see and avoid" to hopefully prevent collision- e.g the airspace above Vale of York or Lincolnshire were general handling areas for several Basic Flying Training stations..on a clear day lots and lots and lots of Jet Provosts spinning/aerobating etc..

Down at low level almost everybody down at 250' agl, with high closing speeds, often with camouflaged aircraft, again only using Mk 1 eyeball for collision avoidance.

[Krystal n chips]

I can think of three alone in this respect.

2x Hunters at Valley.....sadly also killed holiday makers when the remains landed in the caravan park at the end of the runway. 1972 ( I think )

2x Buccs 15 Sqdn out of Karup....no casualties ( apart from some fish ) and a very enjoyable time in Denmark for me...fixing the one than landed safely and fishing ( quite literally, c/o a Grimsby based trawler) the remains of the other out of the sea. 1975

2x Jags 17 Sqdn 1980....sadly one fatality

[DaveReidUK]

There have also been a number of well-known military vs GA midairs over the UK in recent decades.

[fauteuil volant]

The Northwood mid-air collision was that which cost Douglas Pobjoy his life.

[Wander00]

FV - as in the Pobjoy engine?

[fauteuil volant]

That's yer man!

[A30yoyo]

The late Charles Hughesdon had made a coup by getting ABA Sweden's insurance business before and during the war and secured the business of the new SAS conglomerate. His account of the insurance settlement of the collision between the SAS DC-6 and RAF York is related in pp151-155 of his autobiography 'Flying made it happen' (2003) in this scan embed (abridged slightly). (Hughesdon (d.2014 aged 104) is a little inaccurate on the destination airport and pax numbers)

My question is: 'Is the stack separation( raised to 1000ft in 1948) still sufficient for airliners up to 8x the weight, 2x the linear size and with a stacking speed maybe 50% higher?

http://i809.photobucket.com/albums/zz20/A30yoyo/p2x800_zpsofql3gpf.jpg (http://s809.photobucket.com/user/A30yoyo/media/p2x800_zpsofql3gpf.jpg.html)

http://i809.photobucket.com/albums/zz20/A30yoyo/p3x800_zpsendnengr.jpg (http://s809.photobucket.com/user/A30yoyo/media/p3x800_zpsendnengr.jpg.html)

[fauteuil volant]

I wonder if Mr Patterson told his partners what he was requiring from the underwriters? It does rather fly in the face of the concept of partnership and, if witheld from them, that of uberrima fides!

[DaveReidUK]

My question is: 'Is the stack separation( raised to 1000ft in 1948) still sufficient for airliners up to 8x the weight, 2x the linear size and with a stacking speed maybe 50% higher?

In keeping with the rest of your post, if you want to know how risky someting is, ask an insurance underwriter. :O

AFAIK there is no record of the insurance industry having declined to cover airlines who use the standard 1000' hold separation, so I think it's reasonable to conclude that it's not considered to be particularly risky.

And in the UK at least, aircraft in the hold don't use local pressure settings (QFE/QNH) so the issue of incorrect altimeter settings doesn't arise.

[fantom]

Tell me about it...

[A30yoyo]

I'm just making the point that it was considered wise in 1948 to double the stack separation to 1000ft and now aircraft are up to 8x heavier (with stronger wakes), up to 2x larger (linear) and faster in the stack so is the separation still proportionate? Has it been reviewed in the light of airmiss statistics?

[DaveReidUK]

I'm just making the point that it was considered wise in 1948 to double the stack separation to 1000ft and now aircraft are up to 8x heavier (with stronger wakes), up to 2x larger (linear) and faster in the stack so is the separation still proportionate? Has it been reviewed in the light of airmiss statistics?

Airmisses involving aircraft in the hold are extremely rare.

ATC can monitor aircraft altitudes much more closely than they could in 1948.

[chevvron]

I did my ATCO Cadet PPL Course at Cambridge on 1971. My first solo was in C150 G-ATKF which had been involved in a mid air collision with a Varsity out of Oakington a short while before. The instructor who sent me solo told me about the mid air; he had intimate knowledge as he had been the instructor at the time!!

[Wander00]

Chev - happened in 65/66 time too, with a load of baby navs in the Varsity that time, some destined for Basssingbourn. As a result of the accident they were delayed a course or two so I ended up sans nav, and ended up going to 360 as first "first tourist" in Signals Command since I think the War

[Yellow Sun]

Chev,

I don't recall a Varsity v Cessna incident. Varsity v Sea Prince I knew about, but not the one you refer to. Could you provide details?

YS

[Wander00]

Secret profit - sounds close to professional misconduct, but then regulation was much less stringent than now

[DaveReidUK]

I don't recall a Varsity v Cessna incident. Varsity v Sea Prince I knew about, but not the one you refer to. Could you provide details?

https://aviation-safety.net/database/record.php?id=19690821-1

[chevvron]

Chev,

I don't recall a Varsity v Cessna incident. Varsity v Sea Prince I knew about, but not the one you refer to. Could you provide details?

YS
Amazing to read that the Varsity was 'not repaired' so presumably wfu. According to Neville (my instructor), the collision left him without his main undercarriage and he managed a glide landing on the grass at Oakington.
'KF was then trucked back to Marshalls at Cambridge and re-built and returned to use at the Cambridge Aero Club.
Interestingly, Marshalls used to do 'majors' on the Oakington Varsities and Neville (Whittaker) was listed as an authorised test pilot for them along with the other 2 instructors John Page (CFI) and Bob Smythe.
I was also tower controller at Farnborough many years later when a passing C152 from Blackbushe collided with an RAE gliding club glider. We weren't aware it had been a mid air until the ambulance driver the told us the glider pilot was getting hysterical and saying 'that light aircraft knocked my tail off' as the message from the gliding club caravan was merely that 'one of our gliders has broken up in mid air and the pilot has parachuted out'.
It was only when I questioned them after the message from the ambulance that they agreed they had seen a 'high wing Cessna' turn overhead and head towards Blackbushe.
I admit I wasn't looking out of the window at the time as bizjets had finished for the day and s.o.p. was when this happened or when there was a significant gap in bizjet movements, we handed the ATZ over to the gliding club as we weren't staffed to open LARS at weekends in those days.

[CNH]

My father, who has just celebrated his 95th birthday, had a mid air collision in cloud with a Spitfire. At the time he was flying a twin engined aircraft (Hampden? Wellington?).

He managed to land in a potato field but they had to dig 30 ft to find the Spitfire pilot.

[DaveReidUK]

My father, who has just celebrated his 95th birthday, had a mid air collision in cloud with a Spitfire. At the time he was flying a twin engined aircraft (Hampden? Wellington?).

He managed to land in a potato field but they had to dig 30 ft to find the Spitfire pilot.

If you know the (approximate) date, it should be fairly easy to find out what the other aircraft was.

[CNH]

Thanks to research by the gentleman who has recently produced a book on the Wellington, Father has finally found out who it was.