By: ozplane
- 7th April 2014 at 18:11Permalink- Edited 1st January 1970 at 01:00
Re the "invasion striped" RV-4, I think a sale had, or was about to, take place when I saw it on Saturday and if it proceeds it will be based at Top Farm near Royston.
By: AlanR
- 15th April 2014 at 22:21Permalink- Edited 1st January 1970 at 01:00
As I mentioned to Moggy some while back, my brother in law is helping to build a Van at the moment.
I don't know what stage it's at ?, but fairly advanced I would guess, as they've been on it some while.
I will try and get a photo.
I think it will be at OB when finished.
Looks like it's going to be at Hardwick when "eventually" finished and not OB. As that's where he flies from at the moment
The only other info I could get, is that it's going to have a Rotax motor in it.
By: Moggy C
- 16th April 2014 at 07:55Permalink- Edited 1st January 1970 at 01:00
I'd suggest waiting for the AAIB report, except for the fact that I have just completed writing my bit, and there is going to be no formal engineering investigation. So, unless something is discovered in the possible rebuild (not by me) I doubt I will ever know.
It won't come to any surprise to you to learn that I have run the flight over and over and over in my head. Not that this has helped any.
I can tell you what it wasn't.
1) It wasn't a fuel shortage. I know there was something approaching 50 litres / 100 minutes in the tank in use (RH) and even if I had inadvertently switched to the other tank we drained about 30 litres from that tank prior to dismantling the aircraft. It is currently powering a fellow pilot's lawmmower. I have a bill from the Environment Agency for the material used to absorb the contents of the punctured RH tank (Honestly!)
2) It wasn't an engine seizure. The prop windmilled
3) It wasn't a catastrophic engine failure. Not the slightest sound from the front
4) It wasn't the typical finger problem of pulling the mixture instead of the throttle. I was still at full power and my 'mixture' hand was on the panel getting the flaps up before the 100 mph limiting speed
5) It wasn't a magneto issue unless there was an instant double failure
6) It wasn't an inadvertent selection of 'off' on the fuel system. The valve was stiff and unlikely to be repositioned by my knee. A 'first-on-scene' confirmed that the RH tank was still selected when the a/c came to rest
7) Unlikely to have been carb ice. Throttle wide open, full power being delivered, relatively warm day
8) It wasn't contaminated fuel. The airfield had had its pumps and tanks inspected a couple of weeks back by the authorities, nobody else from the field has plummeted
The only vaguely feasible solution is that something came adrift between the RH tank and the engine. The aircraft had just been through annual check. This I did, and didn't interfere with the fuel system, but did check all the lines. My LAA Inspector / Engineer carried out a visual check also, with the engine stopped and with the engine running, cowls off.
Van's with a Rotax? That'll be an RV12 then. Be interesting to see how they perform with just 100hp. Nice aircraft even if the small wheel appears to have been screwed onto the wrong end ;)
Moggy
Lycoming issued and SB a few years back that if an engine ever had a shock loading, the bolt on the aft end of the Crank needs to be replaced, they have had cases before in the States on engines that had prop strikes, although the engines were inspected they didn't have the bolt renewed, these subsequently failed, this holds the drive gear on the crank and that drives the oil pump, camshaft, fuel pump and mags, if it fails the gear isn't driven so the engine will just stop.
I know the engine builder. I will ask him the question when next I talk to him. Thank you Tony.
By: John Green
- 17th April 2014 at 20:31Permalink- Edited 1st January 1970 at 01:00
Re 46
Possible carb iceing.
Can you check the dewpoint on the day ? I've had carb iceing on departure with no prior use of the carb heat - not a good idea ! Throttle wide open. Covered almost the length of the runway before aborting. Failure to develop full rpm. Taxied back to the hold and ran up on carb heat. Departure then normal.
By: Moggy C
- 17th April 2014 at 23:36Permalink- Edited 1st January 1970 at 01:00
I'll see if I can find an aftercast. But the Lycoming has never shown a moment's hesitation prior to this flying in all seasons. But when all the possibilities have been ruled out, whatever is left, however unlikely, has to be the answer
By: Moggy C
- 19th April 2014 at 11:44Permalink- Edited 1st January 1970 at 01:00
Not even remotely scary. Life just gets too busy to be scared.
Firstly getting the nose down to stay above stalling speed, then very quickly choosing the best option for a 'landing' site, then positioning for that site, which needed a much sharper turn than I would have liked, so needed even more nose-down to keep above stall (remember stall speed increases dramatically the more you are banked in a turn), then a futile attempt to flare, thwarted by being too close now to the ground.
Scared comes much, much later. Days even
If I had gone for the 08 overshoot I could have been trapped in the aircraft upside down with avgas dripping all over a hot engine.
If I hadn't kept the speed up I could have spun in, probably a non-survivable accident without a helmet.
By: Moggy C
- 19th April 2014 at 15:49Permalink- Edited 1st January 1970 at 01:00
Smart looking aircraft, though I am surprised the CAA let them get away with the markings appropriate to another country's air force (See the recent 'Flintstone' thread over on FLYER)
Posts: 4,996
By: AlanR - 7th April 2014 at 14:09 Permalink - Edited 1st January 1970 at 01:00
I wouldn't bank on it. Am trying to get hold of a picture of work in progress.
Posts: 1,628
By: ozplane - 7th April 2014 at 18:11 Permalink - Edited 1st January 1970 at 01:00
Re the "invasion striped" RV-4, I think a sale had, or was about to, take place when I saw it on Saturday and if it proceeds it will be based at Top Farm near Royston.
Posts: 809
By: bloodnok - 15th April 2014 at 22:12 Permalink - Edited 1st January 1970 at 01:00
Any news on what might have caused the incident yet Moggy?
Posts: 4,996
By: AlanR - 15th April 2014 at 22:21 Permalink - Edited 1st January 1970 at 01:00
Looks like it's going to be at Hardwick when "eventually" finished and not OB. As that's where he flies from at the moment
The only other info I could get, is that it's going to have a Rotax motor in it.
Posts: 16,832
By: Moggy C - 16th April 2014 at 07:55 Permalink - Edited 1st January 1970 at 01:00
I'd suggest waiting for the AAIB report, except for the fact that I have just completed writing my bit, and there is going to be no formal engineering investigation. So, unless something is discovered in the possible rebuild (not by me) I doubt I will ever know.
It won't come to any surprise to you to learn that I have run the flight over and over and over in my head. Not that this has helped any.
I can tell you what it wasn't.
1) It wasn't a fuel shortage. I know there was something approaching 50 litres / 100 minutes in the tank in use (RH) and even if I had inadvertently switched to the other tank we drained about 30 litres from that tank prior to dismantling the aircraft. It is currently powering a fellow pilot's lawmmower. I have a bill from the Environment Agency for the material used to absorb the contents of the punctured RH tank (Honestly!)
2) It wasn't an engine seizure. The prop windmilled
3) It wasn't a catastrophic engine failure. Not the slightest sound from the front
4) It wasn't the typical finger problem of pulling the mixture instead of the throttle. I was still at full power and my 'mixture' hand was on the panel getting the flaps up before the 100 mph limiting speed
5) It wasn't a magneto issue unless there was an instant double failure
6) It wasn't an inadvertent selection of 'off' on the fuel system. The valve was stiff and unlikely to be repositioned by my knee. A 'first-on-scene' confirmed that the RH tank was still selected when the a/c came to rest
7) Unlikely to have been carb ice. Throttle wide open, full power being delivered, relatively warm day
8) It wasn't contaminated fuel. The airfield had had its pumps and tanks inspected a couple of weeks back by the authorities, nobody else from the field has plummeted
The only vaguely feasible solution is that something came adrift between the RH tank and the engine. The aircraft had just been through annual check. This I did, and didn't interfere with the fuel system, but did check all the lines. My LAA Inspector / Engineer carried out a visual check also, with the engine stopped and with the engine running, cowls off.
Van's with a Rotax? That'll be an RV12 then. Be interesting to see how they perform with just 100hp. Nice aircraft even if the small wheel appears to have been screwed onto the wrong end ;)
Moggy
I know the engine builder. I will ask him the question when next I talk to him. Thank you Tony.
Posts: 8,983
By: TonyT - 16th April 2014 at 11:17 Permalink - Edited 1st January 1970 at 01:00
Moggy
The AD re the crank bolt is
2004-10-14 C
The SB refering is
http://www.lycoming.com/Portals/0/techpublications/servicebulletins/SB%20475C%20(01-30-2003)/Crankshaft%20Gear%20Modification%20and%20Assembly%20Procedures.pdf
Quote from the SB
Since a failure of the gear or the gear attaching parts would result in
complete engine stoppage
Just a thought, if it has detached you may find you can turn the auxillaries, such as tacho drive with the crank not moving.
Posts: 16,832
By: Moggy C - 16th April 2014 at 13:30 Permalink - Edited 1st January 1970 at 01:00
No danger of being able to try that - the wreckage was low-loadered away last week.
Moggy
Posts: 6,535
By: John Green - 17th April 2014 at 20:31 Permalink - Edited 1st January 1970 at 01:00
Re 46
Possible carb iceing.
Can you check the dewpoint on the day ? I've had carb iceing on departure with no prior use of the carb heat - not a good idea ! Throttle wide open. Covered almost the length of the runway before aborting. Failure to develop full rpm. Taxied back to the hold and ran up on carb heat. Departure then normal.
Posts: 16,832
By: Moggy C - 17th April 2014 at 23:36 Permalink - Edited 1st January 1970 at 01:00
I'll see if I can find an aftercast. But the Lycoming has never shown a moment's hesitation prior to this flying in all seasons. But when all the possibilities have been ruled out, whatever is left, however unlikely, has to be the answer
Moggy
Posts: 2,619
By: topspeed - 18th April 2014 at 07:37 Permalink - Edited 1st January 1970 at 01:00
Glad you are ok Moggy !
+8 Gs...what G loads is the plane designed for ?
Speedy recovery Moggy C !
Posts: 16,832
By: Moggy C - 18th April 2014 at 11:19 Permalink - Edited 1st January 1970 at 01:00
+6 / -3g
But the impact was taken by the engine and the base of the fuselage, whereas the limits are more to do with the point at which the wings fall off.
Moggy
And thanks topspeed and you all for your good wishes on and off the forum.
Posts: 2,619
By: topspeed - 19th April 2014 at 10:31 Permalink - Edited 1st January 1970 at 01:00
Was it scary....I mean was it like someone just shut off the electrics in the engine....thus no spark ?
Posts: 16,832
By: Moggy C - 19th April 2014 at 11:44 Permalink - Edited 1st January 1970 at 01:00
Not even remotely scary. Life just gets too busy to be scared.
Firstly getting the nose down to stay above stalling speed, then very quickly choosing the best option for a 'landing' site, then positioning for that site, which needed a much sharper turn than I would have liked, so needed even more nose-down to keep above stall (remember stall speed increases dramatically the more you are banked in a turn), then a futile attempt to flare, thwarted by being too close now to the ground.
Scared comes much, much later. Days even
If I had gone for the 08 overshoot I could have been trapped in the aircraft upside down with avgas dripping all over a hot engine.
If I hadn't kept the speed up I could have spun in, probably a non-survivable accident without a helmet.
Moggy
Posts: 1,628
By: ozplane - 19th April 2014 at 14:38 Permalink - Edited 1st January 1970 at 01:00
Moggy, just to round off the story on the "new" RV-4 at our strip, it is G-BOHW, newly registered to a chap in Fowlmere.
Posts: 16,832
By: Moggy C - 19th April 2014 at 15:49 Permalink - Edited 1st January 1970 at 01:00
Smart looking aircraft, though I am surprised the CAA let them get away with the markings appropriate to another country's air force (See the recent 'Flintstone' thread over on FLYER)
Moggy