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-   -   RAF and Autoland (https://www.pprune.org/military-aviation/607796-raf-autoland.html)

Onceapilot 15th Apr 2018 20:25

Thanks for those details Nugget!
I think your work will have helped make some of the tremendous improvements in approach aids and GPWS the success that they are! :ok:

OAP

Pontius Navigator 15th Apr 2018 20:49

Yes, it was LYN not BZN https://www.pprune.org/rumours-news/...eleased-2.html, read on on following page, same Captain that I flew with into MPA, again a late decision that P2 and FE could not question.I

The second assertion that it was at BZN is true in that Brize was where it landed ]i] after[/i] the prang at Lyneham

EAP86 16th Apr 2018 11:06


Originally Posted by beardy (Post 10118993)
I was led to believe that the Lightning was to be developed as a remotely operated interceptor and that auto ILS and auto throttle were developed for it.

I believe there was a link between the radar and the autopilot in the design with the aim of providing an auto-attack mode but nobody had the b***s to activate it.

EAP

ORAC 16th Apr 2018 11:32

There was a planned datalink to the ground based SLEWC system to feed commands for the pilot to follow - similar to that fitted in the USA between SAGE and the F-106 using the MA-1.

The software was still in SLEWC though and, during my first tour, we still had a monthly requirement to do simulated intercepts using it. It took 2 controllers, one pushing all the buttons whilst the other watched the screen for flight safety. If you were really good you could do 2 simultaneous intercepts - which a single controller could do manually anyway.

It was also so slow that the minimum range at which it would take an inputted intercept was about 100nm. At shorter ranges you moved the fighter label back off the fighter till yo7 had the range and let the label fly the computed course - then manually gave instructions to the fighter to fly it under the label....

Thankfully it quickly dropped out of use.

BEagle 16th Apr 2018 18:28

OR946 as fitted to the Gnat still had 'TAC' and 'DL' selector modes, but the data link wasn't operative. Instead the selections gave 'direct' TACAN indications or as modified by the superb offset system.

The odd student completed a TAC dive in the wrong mode and was surprised by what he saw at the bottom of the dive!

Pontius Navigator 17th Apr 2018 06:48

ORAC, around 1965 we were target for a Lightning using the 'system' but IIRC the data was passed as voice commands for the pilot to follow rather than by link. I seem to remember the dalek type commands like steer 085, accelerate 1.3 mach Now, climb 410 Now etc rather than to smooth mouth music.

ExAscoteer 17th Apr 2018 12:05


Originally Posted by Pontius Navigator (Post 10119540)
Yes, it was LYN not BZN https://www.pprune.org/rumours-news/...eleased-2.html, read on on following page...

The second assertion that it was at BZN is true in that Brize was where it landed ]i] after[/i] the prang at Lyneham

Despite assertions to the contrary, the incident occurred at BZN and not LYN, and is (or at least was) one of the incidents highlighted during the Flying Authorisors and Flying Supervisors cses.

A friend of mine who was on 10 Sqn at the time watched the Tristar fly the visual circuit whilst spewing out a cloud of fuel.

At the time there were no RAF manuals for the a/c so crews relied on a mishmash of letters/memos/loose minutes as well as the British Airways manuals. There was, therefore, a belief that the a/c was cleared for autoland when it was not. Additionally there was also a belief that the narrow beamed ILS at BZN could allow Cat 3.

The TC had flown a visual cct and decided to extend it then turn in and capture the ILS using autopilot. The resultant capture was late meaning that the a/c was well above the glideslope and causing the AP to 'hunt' with a resultant high RoD This resulted in a heavy ldg with a concomitantly large bounce. At that point the TC, rather than attempting to Go Round, retarded the throttles. Since autoland had been selected, this action caused the spoilers to deploy and the a/c literally fell out of the sky causing a second heavy landing (and cracking the mainspar). At this point the TC decided to get airborne again and fly a visual cct to land.

IIRC the coment on the CVR was: "It's not supposed to do that" (!!)

Arclite01 17th Apr 2018 12:34

Timelord

re: Your #15 - it's Neil Williams following the Varsity in to the approach - he's flying a Hastings.

The full story is in his book 'Airborne' ISBN-10: 190655921X

a great read.

Arc

Herod 17th Apr 2018 13:22

ExAscoteer.

Correct me if I'm wrong, but I thought the problem was that the autoland wasn't armed, just the ILS approach mode. That meant the aircraft never entered the "flare" mode, but just kept on going down at the R.O.D. it had when the G/S guidance was lost.

L1011effoh 17th Apr 2018 14:42


Originally Posted by Herod (Post 10121321)
ExAscoteer.

Correct me if I'm wrong, but I thought the problem was that the autoland wasn't armed, just the ILS approach mode. That meant the aircraft never entered the "flare" mode, but just kept on going down at the R.O.D. it had when the G/S guidance was lost.

You're correct. It's a long time ago but ISTR A/L TRACK mode required 30 seconds of being established on the localiser (LOC 'captured' BLACK) before the Autoland system would arm. This didn't happen in the circuit and it happened as Herod describes. ExAscoteer is also wrong regarding the subsequent details - the damage was done to the a/c on the second bounce which was far heavier. The TP disconnected the autopilot on the first bounce (with no 'FLARE' mode) and then pushed the control column forward. This had the effect of removing most of the lift from the wing rather than changing the attitude of the a/c as the DLC (Direct Lift Control) was active with landing flap, which meant the spoilers came out.

It was a source of great annoyance among Sqn pilots that as a result of this, autoland was completely off the agenda thereafter. However, there was some discussion of autoland being allowed for operational necessity when 216 Sqn were based at MXP for Op Deny Force etc due to the winter fog, but it came to naught when the base moved to PMO.

Finningley Boy 17th Apr 2018 16:05

Where's Autoland? Do we have many base there?

FB:)

esscee 17th Apr 2018 16:18

The main problem with the ZE 705 "incident" was that the A/land selection was made at too low an altitude not giving the aircraft systems enough time etc. You will find that on many aircraft nowadays when you make the Approach selection there is a minimum altitude that it has to be selected by, any lower then the system is not engaged. For example by 600 ft radio altitude. This was the problem when a certain training person decided to show off and "look what this aircraft has fitted - Autoland", but he did not know/realise that the selection had to be made above a minimum radio altitude.

ExAscoteer 17th Apr 2018 16:28

I might be wrong on the nitty gritty given that I was using notes taken from my Flying Authorisers cse of some 25+ years ago.


Originally Posted by L1011effoh (Post 10121400)
ExAscoteer is also wrong regarding the subsequent details - the damage was done to the a/c on the second bounce which was far heavier.


However I said:


Originally Posted by ExAscoteer (Post 10121247)
this action caused the spoilers to deploy and the a/c literally fell out of the sky causing a second heavy landing (and cracking the mainspar).

Which rather indicates the damage being done on the second bounce...

L1011effoh 17th Apr 2018 17:25


Originally Posted by ExAscoteer (Post 10121512)
I might be wrong on the nitty gritty given that I was using notes taken from my Flying Authorisers cse of some 25+ years ago.




However I said:



Which rather indicates the damage being done on the second bounce...

I don't disagree with that. No offence meant. It was the 'closing of the throttles causing the spoilers to deploy' that was incorrect - the pushing forward on the control column caused this and was a foible of the TriStar in landing configuration.

I always thought that studying the incident on the FLAC was a bit harsh as it meant the rest of the RAF flying community thought 216 Sqn pilots were 'numpties' - as far as I know, the pilot in question wasn't on the Sqn, but was from Boscombe Down, although I'm open to correction on that.

I've looked online for the BOI proceedings, but can't find it. Anyone have a link?

John Blakeley 17th Apr 2018 17:44

As a technical cadet at Henlow I visited the BLEU at Bedford on April 17th 1962 - flew in their Varsity WF 387 with Sqn Ldr Bray as the aircraft captain.

Prangster 17th Apr 2018 20:07

'Twas really weird as non aircrew jumpseater I was rather entranced when the BLEU Pig wandered in seemingly of its own volition with the pilot equally seemingly taking no damn notice

Cornish Jack 17th Apr 2018 22:43

Re. the tri at BZN, I was tech instructing on the Tristar at BA at that time and we were told that it was down to an attempted VERY late a/l selection - quite specifically contrary to the Ops Manual instruction. I kept a copy of the report for some time but it has disappeared in one of a multitude of 'backup' storage devices!

Blacksheep 18th Apr 2018 16:48


The aircraft basically flew the ILS, then at approx 50’, the throttle closed and the aircraft flared a bit.
Yup! That's a pretty good abbreviated description of a Cat IIIb Autoland system. It leaves out all the confusing technical details and cuts through to the essentials. ;)

Q-SKI 18th Apr 2018 21:07

I was on a Course at Brize on that particular day of the “heavy landing” and walking up to the mess with an army colleague who looked up and commented “its a bit poor the Tristar is dumping fuel in the circuit”. My reply was to hurry up and enter the mess, when asked why, I replied that if we didn’t see any more we couldn’t be a witness at any subsequent BOI!

Herod 19th Apr 2018 10:13

Q-SKI. My take was different. If you witnessed the accident, you couldn't be a MEMBER of the BOI. A much more onerous task.


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