SGIAN DUBH

It depends what you call credentials, I don't have formal aeronautical engineering qualifications however I have been studying the subject since 1976 during which time I have completed fifteen aircraft, not completed two others and am nearing the completion of the current one (DooMaw, my avatar). The completed ones were all successful and fly well, the varying experiences I had with 'tuning' some of the earlier ones, and abandoning two of them are all testament to the learning curve. All are/were of my own design. Experience of that kind, and over four decades, does provide valuable real-world experience that some might say amount to a little more than 'well meaning findings', but by all means take my observations as you see fit and do with them as you will ... :-) .

I always take what others say or suggest as Good Sound Advice offered with the best intentions, the problem in the UK is " Everyone is an Aircraft Engineer until the engine starts " Thus why I look further afield for advice and analyse whether the person is a Waffler or an informed font of knowledge, I am sure you are the latter "

 

I didn't say the Quaich's stall speed would be much above the 30-40kt region, I said the tail control surfaces looked like you might have a minimum controllable speed well above the stall speed. I said the elevator wasn't likely to have enough authority to bring the mainplane to the stall. That results in the minimum controllable speed being well above the stall speed because when you reach full rear stick travel the lift and moment provided by the elevator isn't sufficient to overcome the moments provided by the CG being ahead of the Centre of Pressure (CP), the pitching moment of the airfoil and any additional pitching moment provided by extending flaps. It all adds up to a plane that won't fly as slow as it could, if you could bring it to the stall..

I take your points & will bank them for future recall during testing......you may well be right in what you foresee, I hope you are wrong but you are certainly putting reasoned doubt into my mind.

 

It's a much misunderstood thing, people bring the stick back to the stop, the plane gets slower until eventually it reaches a minimum flying speed and 'mushes'. How often have you heard people say their plane is very kindly in the stall, it just mushes? Fact is, it hasn't reached the stall at all. Now, that doesn't mean the assurance you were given that "the Elevator has more than enough authority to ensure a controlled landing" is wrong, it means that the landing will need to be much faster than you expect, because if my assessment of the elevator's size is correct, then you'll run out of elevator authority way above the stall speed..

The Stall will be fully explored, I won't be settling for Mushing... I want to see a FULL STALL ( It will be done at Altitude for safety )

 

And - earlier, in the Sgian Dubh thread, you said you had an aerodynamicist who was "the most respected aircraft engineer in UK" or words very close to that, involved in this program. Above you said "Until it gets test-flown ( in the air ) it will be an unknown stall speed". That is a mystery ... how can you have such a highly revered person on the team and he doesn't seem to know how to do the most basic of aeronautical calcs i.e. the stall speed prediction. Presumably you know the airfoil section, the wing area and the weight of the aircraft? That, and a set of polars for the section (available on many sites online) are all you need to predict the stall speed with great accuracy. Determination of similar for the HS, factored by the tail moment, would tell you for certain whether the elevator will have the authority to fully stall the mainplane or not ... it's basic stuff..

My Aerodynamicist will be doing the calcs ( to see how they differ from the designers scribbles ) He is currently wrapped up in the Sgian Dubh & I don't fill his pockets with enough dollars to have him looking at more than 1 project at the same time. ( He would look at figures if I asked him, so when I have both the aeroplane & all the spreadsheets in front of me I will be in a better place to ask him questions ) The Vto is supposed to be 37.4mph ( 32.52kts) So I am hoping that a Touchdown at 30kts is feasible....... The Cruise is supposed to be 70mph (61kias) to 105mph (91kias ) with a VNE of 110mph

 

Assurances are good - but the proof will be in the pudding, as they say, and the actual fact will be very easy to find out as soon as you start taxi tests, so the tail-lift thing is a non-issue - you'll know the answer before you ever need to get airborne. If the one providing the assurances has conducted a lift coefficient and moment calc for the HS and VS then it would be useful to attach it here, if you like. Second opinions would likely be forthcoming and where controllability and test-flying is concerned it doesn't hurt to have a few of them..

The builder/designer has reams of calcs on file that I will pay full attention to when I need to commence testing.

 

Just my opinion again - but a well maintained 2T with a knowledgeable operator can be very reliable. In my experiences the key issues are - maintain full throttle in the climb, a lot of folks like to 'back off a little' and that leans the mixture considerably which makes it run a lot hotter and risks nipping up. Make sure you don't have air leaks in the induction, either at the rubber mounts after the carbies or direct to the crankcase (via the fuel-pump pulse line is a classic), they both lean the mixture with disastrous results. Avoid low idle speeds on the ground, the 'rattle' breaks the crankshafts. Avoid long low throttle descents, it shock-cools them and that can crack things, or they can oil up the plugs and stop, or oil-injected ones can run with insufficient oil in the mix. Use 2T oil for air-cooled 2T engines, not for water-cooled engines like outboard engines, the oil is designed to burn at different temperatures i.e. air-cooled engines run hotter so oil for water-cooled engines burns too soon if used in air-cooled engines. HIH..

We are both singing from the same hymnsheet on the 2 STROKE Operations, I am not a 'back off a little' in the climb pilot......... I am going to have a Rotax specialist look at the 447 BEFORE I even start it up.

 

I didn't say the forward position of the mainwheels was 'dangerously tricky', and neither did I mean that it need be any kind of problem. What I was on about was that it would have two effects - first it would make the weight on the tailwheel greater than if those wheels were further aft, consequently the 'down' elevator has more work to do to lift the tail in the take-off run, and secondly the further the wheels are ahead of the CG, the more work the rudder has to do in a crosswind. In both cases the forward wheels position does a dis-service to the already very marginal tail flying surfaces' effectiveness.

I will be wary of what you have said because I am used to 200-300hp Engined Tailwaggers so I always have had bags of power on tap to lift the tail & aerobatic surfaces that are substantial.

Thank you for your input ;-)

 

 

A couple of observations that you might want to consider during your testing -1. If it was mine the elevator and rudder would have much more area. The area they have at the moment is more typical of an aircraft with a stall speed in the vicinity of 60kt than the 35-40kt I imagine this will have. Consequently it's very likely that the elevator will run out of authority a fair while before it could bring the mainplane to the critical angle and stall it, so you may find your landings will be a good bit faster than anticipated, or is desirable.

H.I.T.C, Do you have credentials that back up your opinions or are they just ' well-meaning ' findings? I only ask because I seem to be getting different opinions from here to there ;-) Until it gets test-flown ( in the air ) it will be an unknown stall speed though I am almost certain it will be in the 30kt area ( I certainly hope so because it needs to be to comply with SSDR ) I am assured the Elevator has more than enough authority to ensure a controlled landing.

 

Similarly the elevator may not have sufficient authority to lift the tail during the take-off roll. If the aircraft has flaps and you use them on take-off then they would move the centre of pressure of the mainplane aft and that would help with the situation very considerably. If you don't have flaps, or don't use them for take-off, and if the engine has sufficient power to overcome the drag and reach take-off speed in the three-point attitude (with a 447 it should have) then you would be likely to become airborne in the almost-stalled attitude. Once the wheels are off then you'd want to lower the nose and build speed rather promptly or risk a wing-drop (lowering the nose would happen 'automatically' if you maintain stick forward as it lifts off, of course, though that's not entirely intuitive) ... this situation of perhaps not being able to lift the tail prior to take-off is made worse by the position of the mainwheels which appears to be a little forward of the leading edge (in level flight attitude) - right below the leading edge is more 'usual'. The condition would be improved by ensuring a CG toward the forward end of the range but that could be a bad trade-off in terms of increasing the landing speed even further because of running out of 'up' elevator authority even earlier.

I am assured the Elevator has more than enough authority to ensure a controlled tail lift in the take off run. I have very little confidence in 2 strokes but as a 447 /503 is the only realistic option for this aircraft I am stuck with that as a powerplant....... I have ample hours on Taildraggers so I don't envisage that I will have any problem getting the tail up ( I doubt my Test Pilot will have any problems either ). I am intrigued by the mainwheels reference.... I have flown many Tailwaggers with mainwheels ahead of the Leading Edge & they are more tricky but not dangerously tricky. I will be looking closely at the CofG & if it can be moved toward the front of the range it will be adjusted.

 

2. It has a tall rudder, and some of its area below the HS, which is very good, but I'd venture to say that you might find it has rather limited capability in cross-winds. The large amount of fuselage side-area behind the CG, the forward landing gear position and the smallish (narrow chord/high aspect ratio which stalls at a lower Reynolds number than a lower aspect ratio would) rudder all combine to limit the aircraft's cross-wind ability, so I'd be leading up to cross-wind landings gradually.

Again the Crosswind capability will be explored closely before we set a figure that we are happy with..... One of the beauties of our UK SSDR Category is that " it is a licence to explore the parameters of your aircraft "

 

The UK CAA have even said " SSDR allows Aerobatics if your Design is capable of withstanding the G forces associated with Aeros "

 

I won't personally do Aeros in any SSDR that I currently operate, might be tempted in a Phantom Ultralight if we manage to acquire one ;-)

 

Currently having a bit of grief getting a Kolb Twinstar through SSDR because it is ex LAA/PFA & it looks like the LAA are reluctant now to have too many LAA aircraft moving onto the SSDR category.

 

 

Just getting ready to commence the Quaich Flight Testing ( Collection of the Microlight is imminent, once our Trailer is emptied of the Building Supplies for the Holiday Home projects ).

 

The Quaich has a Rotax 447 engine & has an empty weight of 184.2kg & will be cleared to 300kg under the UK SSDR acceptance.

 

We are limiting the Pilot weight to 86kg to allow for 30litres of fuel to be carried ( the tank will be replaced by a 40ltr Tank as calcs will allow 40ltrs with a 86kg Pilot )

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Phil Perry.......Knowing the Aircraft ( having rejected buying it for reasons that I can't disclose at this time because of the accident investigation ) I too think it would be prudent to await the AAIB report & see whether what your straight talking instructor says tally's up with what I believe caused the accident.

 

The Accident Picture also points towards my theory.

 

 

 

The Sgian Dubh will be getting fitted with a Mid-Life Rotax 503 very soon ( just having the engine checked for serviceability ). The Sgian Dubh is going to Newquay St Mawgan for hangaring.

 

The Quaich is ready for test flying, just waiting for a UK registration to be assigned & then it will commence the flight testing.

 

 

Well ... if you want another opinion I'd say there's some considerable degree of confusion in the discussion above, caused by lack of correct terminology SD.The fella from BMAA expressed his concern about the transfer of the lifting load carried by the wing outer panels to the wing centre section - his assertion is that he doesn't like the discontinuous spar caps and considers the ability of the 'tenons' to carry the load to the centre section to be suspect.

 

He may, or may not be right, it all depends on the connection between the tenons and the spar caps in the outer wing sections, and for how far they overlap internally, and how they actually connect to the centre section. Based on the very limited (read 'quite insufficient') information in the sketches in the pdf, I concur with his concerns. It's not the prettiest way to hold wings on ...

I am always open to another opinion....... I am putting a lot of faith in Hugh's build quality & being face to face with him, everything he says seems plausible ( it is a bit like Rocket Science to me )

I have some very knowledgeable engineers around me who understand the flying wing concept , so I am letting them move this forward from a flight testing aspect.... I do have to consider that I will be putting a flying friend into the HOT SEAT & it could be a load on my shoulders if anything goes wrong. I think the messages in my previous post are not seen in full context as I was also discussing it by phone at the same time so that in reality is only 60% of the story ;-)

 

The Quaich which I will be playing a more active role in the Flight Testing seems like a conventional 3 axis microlight so I am fairly chilled out by this project.

 

I am looking at every single detail of the Quaich documents etc so that it is engraved in my brain what everything is on this SSDR microlight.

 

I am keen for Hugh to see his Sgian Dubh design & his Quaich design take to the air...... Thankfully the Iolaire has already flown so I don't have the pressure of getting that into the air ( Our CAA are not keen to allow that into SSDR as it is a big microlight that I doubt we can lighten down to 178kg safely )

 

 

Today seemed to be a Lucky Day for me.

 

I was a little bit concerned by the remark

 

 

 

"There are some very questionable design features in these drawings. For example, drawing L2-W4 shows a very unconventional wing root joint in which the spar caps are effectively discontinuous, and the load is transferred purely through the ‘tenon’.

 

The stress calculation at the end of the document raises more questions than it answers, and leaves me unconvinced that this design feature is in anyway satisfactory. "

 

 

 

so I had a Trusted Aircraft Builder/Restorer look over the Wing Loading Calculations & this was their informed response :

 

 

 

(PJK)Hiya, do you understand wing loading calcs?

 

 

 

Try me.

 

(PJK) Your friend BEN SYSON has queried the wing integrity of the Sgian Dubh......he says he is concerned by the calcs

 

 

 

Give me the chord,the length of the wings,the all up weight of the aircraft with fuel,the aerofoil section and the deepest part of the aerofoil ie the centre of pressure.

 

 

 

 

Let me study it later.

 

(PJK) http://www.hughlorimer.co.uk/sd_drg.pdf

 

www.hughlorimer.co.uk

 

hughlorimer.co.uk

 

 

 

I would very much doubt if the wing loading is too high.

 

(PJK) that is the PDF for Sgian Dubh calcs ( everything is there in B&W )

 

 

 

Is that the idiot who does not know the difference between a rib co-ordinate and a GPS ?

 

(PJK) yes wink emoticon

 

 

 

Sounds like someone is playing a blinder,mind you they are all blind there ?

 

Canards have higher wing loadings anyway.

 

(PJK) I am only looking for an opinion......I won't hold you to what you say.....just a man is going to fly the SD & I don't want him to fold a wing wink emoticon

 

 

 

Thats ok I will give you an honest opinion.

 

(PJK) The Sgian Dubh is not a Canard..... it is a Flying Wing.

 

 

 

Same but different,lots of wing area.

 

 

 

They are just trying to place obstacles in front of you.

 

Look at the flying bricks like Dykes Delta.

 

I cannot open that strange file Peter ?

 

It says file association unknown,drat.

 

(PJK) open the pdf

 

page 21 &22

 

 

 

OK got it.

 

 

 

 

Never mind the pdf will do,let me take a quick glance now.

 

(PJK) thanks wink emoticon

 

 

 

Its built like a tank,basically 137 square feet total + 41= 178 = 1.37 lbs sq feet at 300lbs all up weight at a 1g loading,its stressed at 1.68 /ton inch for 6 g,whats the problem ?

 

And that is just the spars,with the torsion box construction its well in.

 

(PJK) OK Thanks wink emoticon

 

 

 

I am very impressed with his drafting and designing skills,he has stressed at a level well below what is actually needed for safety,given the deep wing section and slow flying characteristics even in a severe buffet its a safe machine,I really think they are trying to hoodwink you Peter.

 

 

 

They said the Quickie was a high wing loading in the early days and look at the thickness of that wing by comparison.

 

yes I know

 

 

 

I would get back to him and query why he thinks the wing loading is high ? especially given the data supplied and that the designer has stressed at 6 g in his calculations.

 

(PJK) I know........over-engineered into the build

 

 

 

Yep.

 

I would be happy operating a delta with those specs.

 

(PJK) me too

 

 

 

That is going to leap into the air.

 

(PJK) yes

 

 

 

And you know what to do if the worst comes to the worst ?

 

(PJK) what?

 

 

 

Place the machine in flying position,load the wing up with sandbags at strategic points across the span and chord and do a static test,just like they did in the early days of flying,that way you can prove they are very wrong.

 

(PJK) We are going to do the inverted wing loading

 

 

 

Good idea,if they break they break,but I doubt if they will.

 

(PJK) I DOUBT IT AS WELL

 

 

 

Invite his lordship to be the observer when you do it,they have the facts well recorded what more do they want ?

 

 

So now I am more than happy that the Sgian Dubh Wings are substantial enough for the safety of the aircraft ;-)

 

 

 

Then the day got even better when I also received this reply to an email I sent to another Aircraft Collector :

 

 

 

Yahoo! Mail

 

17:02 (3 hours ago)

 

 

 

 

 

 

to me

 

 

Peter,

 

I have a 503 that you would be more than welcome to borrow for your testing.

 

It has been sitting in my workshop for some time and would probably need checking over.

 

I,m not too sure if I have a 447 to loan I would have to check, it could be a 377.

 

I may be able to arrange something with regard to St Austell, it is a pity as I delivered a Tiger Cub to my friends son at St Blazey last week.

 

I spend 4 days each week at St Mawgan which may be a better pick-up point if convenient for you.

 

Let me know what suits.

 

Regards,

 

Ian

 

All in all, everything is coming together...... I have also been given clearance to start on the Quaich Project now...... That will be flying within a Month.

 

 

 

Having asked the BMAA ( BRITISH MICROLIGHT AIRCRAFT ASSOCIATION ) if they still have access to the submissions for the Iolaire I received the following response from them ( Not sure why the Sgian Dubh came into the content as it wasn't a concern before getting their email :

 

Ben Syson via gmail.com

 

10 May

 

 

to PJK

 

 

Dear Peter,

 

Iolaire

 

We have an historic file on the Iolaire.

 

It has not been opened since I have been at the BMAA (2006), and I am unaware of its contents.

 

An ‘experimental’ 2-seat Microlight can now be test flown on E Conditions.

 

Details are on the CAA website: http://www.caa.co.uk/General-aviation/Aircraft-ownership-and-maintenance/Experimental-aircraft/

 

Although an ‘experimental’ single-seat Microlight can be legally flown without any airworthiness ‘approval’, it doesn’t mean it’s necessarily a good idea.

 

It is legal solely because the risk to third parties is very low; it is not a judgement in any way on the risks posed to the pilot by this activity.

 

I would strongly recommend using an E Conditions Competent Person - and with careful consideration of the E Conditions guidance - even if the aircraft is SSDR.

 

Sgian Dubh

 

I have noticed that you have also become the registered owner of the Sgian Dubh G-CJPK.

 

Some sample drawings of this type are available on the internet: http://www.hughlorimer.co.uk/sd_drg.pdf

 

There are some very questionable design features in these drawings.

 

For example, drawing L2-W4 shows a very unconventional wing root joint in which the spar caps are effectively discontinuous, and the load is transferred purely through the ‘tenon’.

 

The stress calculation at the end of the document raises more questions than it answers, and leaves me unconvinced that this design feature is in anyway satisfactory.

 

Again, I would strongly recommend using an E Conditions Competent Person and the E Conditions guidance, even though this aircraft is SSDR.

 

Regards,

 

Ben

 

Ben Syson

 

Chief Technical Officer

 

British Microlight Aircraft Association

 

01869 336 006

 

[email protected]

 

I am now looking for opinions on the Wing Loading Calculations on Page 21&22 of the PDF.

 

Obviously under our SSDR Category I/we can just go ahead & do our own flight testing, however I am now considering the E Conditions Test Pilot process if I get enough plausible reasons to follow that mindset.

 

 

SD, I can't quite agree with your 'order of magnitude' for the three projects. I'd say the Iolaire is likely to be the most benign of the three, probably closely followed by the Quaiche. That said, I'd want to check the Quaiche CG carefully because unless it has a disproportionately heavy engine it looks a bit stubby in the nose so the CG might be a bit aft - that all depends on the weight of the aft fuselage structure of course.

Whilst I am open to your opinion on which one you think would be most benign I am going to stick to what my Aerodynamicist has implied..... As he is regarded as the best aircraft engineer currently in the UK.

 

I'd think that the real challenge will be the Sgian Dubh. With the weight in it's ends (pilot up front and engine down the back) it's likely to be very nasty if it ever entered a spin (would possibly want to go flat) and will probably have very limited pitch and directional stabilities since it appears to lack any effective sweep in the mainplane. It's not very clear in the photos, but from the little you can see it doesn't appear to have much, if any, reflex in the airfoil section either, if that's the case it could even be pitch unstable.

I am glad that I am not the Test Pilot for the Sgian Dubh, it needs either a better pilot than I am or a more adventurous pilot than I am ;-) I have every faith in my choice of pilot & am pleased that he is also involved in the final checking before flight...... his enthusiasm for Flying Wings is second to none ;-)

 

I hope I'm shown to be wrong, but the only plane I'm aware of that got away with similar design features was the Pelican, and you can see how much effort has gone into getting the major weights as close to the CG as possible, and it has a lot of reflex -

[ATTACH]42900[/ATTACH] [ATTACH]42901[/ATTACH]

 

Hugh Lorimer has done so many calculations on the Sgian Dubh that it has the CofG marked on the side of the fuselage & also the aerodynamic CofG marked for reference ( weight & balance calcs show an inbuilt stability )

 

Though I've not seen a true planform view of it, the Iolaire would appear to be a very conventional canard design albeit rather difficult to access the rear seat.

If we succeed in getting the Iolaire into the SSDR ( single seat de-regulated ) category access to the rear will be disregarded ( it will be a baggage locker )

 

I question the opinions of your 'aerodynamicist'. If you have doubts about the design I wonder whether you might do better to get the opinion of an aeronautical engineer. Aerodynamicists rarely know much about 'whole aircraft'. I'm not talking out of my ass, I know two of them very well, one is my nephew. Both were trained in Universities in England and whilst they are exceptionally knowledgeable about fluid flow around and over specific shapes, neither of them has any knowledge whatsoever about aircraft. My nephew read for his Degree because he was fanatical about the McLaren F1 team and wanted to work for them, he can tell you the most precise details about the fluid dynamics of the flow into or out of the radiator ducts for instance, but wouldn't know much about a canard's overall design requirements.

My Aerodynamicist is probably better qualified to answer my queries than someone who studied fluid dynamics for McLaren F1 ;-) I think McLaren F1 need to go back to the drawing board with regards to their streamlining & fluid dynamics theorum ( or steal the Mercedes blueprints )

 

Referring to your aerodynamicist's comment above - well of course the canard could adopt a lower incidence than the mainplane - it's a control surface, and when you want to put the aircraft into a dive the canard will have a much lower incidence than the mainplane, but so what? In a dive the mainplane's not going to stall is it? Going back to basics you will recall that the best indicator of the potential to be approaching a stall is the stick position, when the stick is back you may stall, right? So when the stick is back the canard is at a high incidence compared with the mainplane isn't it? So the canard will stall first provided the CG is in the right position for a canard-style aircraft.

The concern with regards the Iolaire is the Canard is an all moving Canard..... My aerodynamicist 'thinks' we should make the Canard a 75% solid structure with some positive incidence and have a 25% movable elevator integrated into it.

 

As long as the CG is well forward of the mainplane, and consequently the canard is much more heavily loaded than the mainplane then the canard MUST stall before the mainplane, if the plane is capable of flight at all, and I don't see any reason why it wouldn't be capable.The underlined items previous are the critical factors for safe canard operation. Many people don't understand canard dynamics properly and consequently make quite erroneous comment about them, on occasions.

The Iolaire is the only one of Hugh's designs that has previously flown, having watched the video & got a miniscule bit of feedback on it I am inclined to think that the canard needs to be structurally secured with an elevator section

 

Of all the aircraft I've flown, the one I found to be the easiest, most forgiving and what I would describe as 'completely docile' is of very similar fundamental design to the Iolaire, the American Aircraft Falcon, even Chuck Yeager liked it -[ATTACH]42903[/ATTACH] [ATTACH]42904[/ATTACH]

I too have flown a Falcon XP as well as the Vari Viggen & Varieze..... I had a quick flight of a Rutan Defiant as well so used to Canard types.

I think I will just set my goals on me doing the Quaich Flight Testing & leave the Sgian Dubh to my assigned team & then build another team to fettle the Iolaire when Project 3 comes along.

 

I have no control over the way we get the projects..... Hugh wants the Sgian Dubh to take to the air before we start flight testing the Quaich, then as the SWANSONG the Iolaire will be restored to flying capability and tested fully.

 

 

yes, Iolaire flew.there is a video which details hugh lorimer reports and shows the tests of all flights.

Yes it has flown....... I have watched the video & spoken with Hugh on the subject...... I think it needs a bit of redesigning according to my Aerodynamicists.

 

The BMAA should have copies still on file of any structural reports that Hugh submitted - I honestly can't remember if it complied or not to Section S. Clearly I also need to find a competent test pilot prepared to take on a flight test evaluation and iron out any handling bugs - and I think it's likely some will exist. In particular I have been very strongly recommended that I test a wind tunnel or radio control model with the same all flying canard geometry to evaluate stall and stall recovery related handling characteristics before any attempt to fly the aeroplane. Specifically my Aerodynamicist was very concerned that the canard could adopt a lower incidence than the mainplane, so there was potential to achieve a condition where the canard was unstalled and the mainplane stalled, leading to a tailslide from which it was not possible to show by analysis that it would recover.

 

However, it's clearly flown at least once without killing anybody, which is a start. Nonetheless, I'd personally treat flying the Iolaire initially as a high risk flight test programme, with all that implies, as a matter of basic survival. Vaughan Askew's book "Flight testing homebuilt aircraft" and the FAA's flight test guide AC90-89 are useful guides to those processes, but ultimately you need it test flown by somebody who is a trained test pilot backed up by some robust preparation and planning - I don't want to make it up as I go along or I probably will die.

 

 

I wish you success in this endeavor and we are all very anxious and hopeful for a peaceful flight test.perfect also was the decision to invite hugh to participate and witness all these events.

dream come true.

Altair, It is only right that we invite Hugh to the Flight testing of the Sgian Dubh........ I think the Sgian Dubh is the most interesting of the LORIMER PROJECTS ( and probably the harder of the 2 I am interested in to fly )

The Quaich will be a very easy to fly aircraft, not that concerned by that at all........The Iolaire is the one that the verdict is out on !!! Some Aerodynamicists think it will be as stable as a dart & other Aerodynamicists think it will be a bucking bronco........time will tell on that one ;-)

 

 

Sgian Dubh ( PROJECT ONE ) likely to be a Handful.

 

 

Quaich ( PROJECT TWO ) Easy to Fly in my opinion

 

 

Iolaire ( PROJECT THREE ) This one is going to be a REAL CHALLENGE as it has already been subject to close scrutiny by the BMAA & I doubt will fit into the SSDR category without a lot of fuss.

 

 

It is very good to see the stamped happy smile on you face hugh Lorimer ...

Hugh was certainly extremely HAPPY to see his Sgian Dubh going away to Cornwall for final checks & then commence Flight Testing ( when we locate a working 447 or 503 engine ). We have agreed that Hugh will be invited down to witness one of the Test Flights.

 

Hugh was impressed by the guy who will be doing the final checks & flight testing....... The Trailer has definitely seen better days, we flipped a coin as to whether to just go and buy a trailer or whether to repair the trailer ( The trailer had 'makeshift' repairs to enable it to get to Cornwall done by my Engineer ) I won't go into too much detail but it involved Welding & structural work to make it only mildly dangerous as opposed to suicidal to use.

 

Pictures of it at Cornwall :

 

 

 

 

Pictures from the Transportation to Cornwall from Mauchline ( Pt1)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

And to confuse us you are using a time machine to do the transport 1 month in the past??? And who is rebuilding? You are in Edinburgh and Corwall is pretty much as far away from you as it is possible to get while staying in the UK ...

The timestamp of 4th April should have said 4th May ( my mistake)

 

Yes I am based in Edinburgh, I am also based in London, I am also based on the IOW.

 

The aircraft is fully built ( excluding the engine ) but for reasons of it actually having been built in 1999 we are going over everything to ensure it is all still good & airworthy still.

 

The Team overseeing all this work are a specialised team of Aviation Geeks from Cornwall who get uber excited about Flying Wings & have a wealth of knowledge on Flying Wings ( Me, I am just the numpty who wants for Hugh to see the Sgian Dubh take to the skies )

 

The Sgian Dubh briefly flew today on the transportation from Mauchline to Abington...... the winds were 50-60mph & it left the ground in a gust whilst we were enroute down the M74 so we had a 50mph forward speed & a 50mph crosswind briefly ( it made that sector of the trip very interesting. )

 

 

Sgian Dubh is being prepped for transportation to the Rebuild Centre today, it will be roaded to Cornwall on 4th April 2016 & then Reassembly commences ;-)

 

Will post pictures on my return from this epic trip.

 

To confuse all Aircraft Spotters who will be gawping at it on the journey down we are leaving the G-MEXP registration on the side etc.

 

G-MEXP was a Ficticious registration placed on it for the Microlight Shows ( M for Microlight / EXP for Experimental. )

 

 

 

Having seen the HypeR at Popham. It looked quite crap to me, it does have some neat bits though......especially the adjustable seats! Very clever how they've got the pilot's seat adjustable fore and aft just like a car, and the rear one can be adjusted up and down. Bill Brooks said the pedals are also adjustable, so that one size plane fits all possible pilot shapes. Neat! I wasn't too impressed with the open bit at the back near the radiator. That bit looked clunky to me, and the method of adjusting the amount of cooling by moving a large flat plate up and down in front of the radiator also seemed less than properly thought out. Bob Hood suggested they should box it in like they have with the PulsR and have vents on the side or underneath that could be opened and closed as needed.

 

( pics by various photographers )

 

 

 

 

 

 

 

Today it hasn't grown any prettier ( you know how a baby looks even more gorgeous the day after birth ) Well this is still fugging ugly ;-)

 

 

I am not quite sure why.......but the radiator is on a cable pulley system so it can be pulled towards the white uprights?

 

I am curious why there is a scoop just behind the wheel? I hope that isn't the intake for the airbox ;-)

 

 

Mutton dressed as lamb.What is the price, as a matter of interest?

They haven't disclosed a price yet........... I suspect they are too scared to tell anyone yet, I just hope this isn't the Product that P&M are thinking is going to pull them out of the financial abyss they are sitting in.

 

What I see is a Quasar revamp with the rear section of a PulsR morphed onto it.

 

 

AMAZON, Gezzzzzz wrong platform for filming Id say, open area shoreline large lakes, is what this FIB was designed for

I have a Polaris FIB582 G-CIXI that is operated by a Wildlife Conservation Supporter in Weymouth & an acquaintance is operating a Polaris FIB582 in Crete.

Both these are operated in Open Waters & neither are classed as open area shoreline large lakes.

 

These are very capable FIB's

 

 

 

Today P&M Aviation unveiled the P&M Aviation HypeR @ Popham Airfield (30/04/2016) during the opening of the Annual Microlight Trade Fair.

 

I am not someone who gets that excited about Flexwings, so the unveiling wasn't the highlight of the Event for me.

 

I will let those of you who are interested in Flexwings see the Microlight & I am interested in your opinions to see if they match mine?

 

 

 

 

I think the hedge did it.I wonder if he did everything right, even dodging the power lines, and just found himself with that do I? or don't I jump the hedge?

The simple answer is : " Yes, He did it right "

Maybe I am over-analyzing this from the comfort of a relaxed position on a soft sofa, (which is something Kev didn't have during that flight) so I am convinced "he did it right"

 

 

 

In the video @ 1m45 he is at 302ft QNH having descended from 378ft QNH @1m40 to 329ft QNH @ 1m43. A turn around the tree @ 1m46 at 283ft QNH to establish himself on final approach to his impending arrival spot looked (from the comfort of a sofa looked to be extremely close to the branches ) @ 1m48 at 250ft QNH he was fully established on final & committed to what was about to unravel...... 2seconds later @1m50 he was 224ft QNH & possibly sensing " I am nearly there !!! @ 1m51 the impact with the bushels was imminent and at this point with 61mph of groundspeed I think ( from the comfort of a sofa ) I would have converted a bit of speed for a bit of height to clear the bushels ( Note it is an opinion based on hindsight & not what I might have done if in Kev's position at that time, at that exact time I strongly believe I would have done exactly what Kev did. )

 

 

 

The interesting point is throughout the entire final section of the video a 9% descent profile was set up ( which looks to resemble a 948fpm descent rate or 15.8fps )

 

 

 

 

 

 

bit unfair to say shoehorned onto council ... but yes, RAAus is not the only flying org that has a history of ignoring their own rules ... and when one candidates nomination is ignored and that candidate is a solicitor the exec can pretty quickly discover that the rules and members have bite

Kirk,

I am fully aware of the Deception & Malpractice that the Rats on the BMAA Sinking Ship can stoop to.

 

I was not at all surprised when in the last BMAA Elections the Deception tactics were put into play again ;-)

 

It has IMHO backfired on them.... just before the Election they co-opted Spencer Harvey ( in a veiled attempt to stop me getting elected by reducing the number of places from 4 to 3 ) so Spencer has to stand in the election this year. Their idea was to ensure that Dave B & Rob G will be re-elected ( by hook or by crook ) & then have Deepak M & Rick fighting for 3rd place, it all went very wrong when Deepak swept the board with the highest amount of votes with Dave B trailing behind by 22 votes & then Rob G coming 32 votes behind DB.

 

I have no doubt that they should have left it at 4 spaces as I believe they thought Deepak would have came 4th or 5th, I know you weren't keen on Rick but I think the BMAA is now sinking faster now he is ousted.

 

Will I ever stand again? I might out of devilment but only because I know it gives Dave B sleepless nights ;-)

 

I am in a bit of a Quandary because I have a part share in a CFM Streak Shadow that is based where 'Grim' flys from & the Majority shareholder in the Streak is about to embark on an epic trip with Deepak soon in an Electric Pipistrel.

 

 

Well Peter think about BMAA elections (you've tried a few) and you'll recall me as a winner in one of them ;-)

Ah Hello Kirk ;-) The "Shoehorned into a position on Council " after it was announced that both Rick Goddin & I were duly elected ;-)

Probably the best thing that has happened to me was you getting elected ;-) I had a lucky escape ( dodged a bullet springs to mind )

 

Anyway this is far removed from the BMAA so let's not reflect on the pettiness of them, the BMAA have no place now in my day to day life, the BHPA have my best interests at heart when it comes to SSDR.

 

Good to hear from you again ;-)

 

 

I agree the video is great sharing.I see there are two power lines showing the direction of the wires (pause the video near its end) that would account for the veer to left at the end to avoid the power lines that ended up bowling over the low scrub.

 

The comments re airspeed in other threads should alow fr the lag in the AIS indicated reading.

 

Certinaly an acceptable outcome.

 

Cheers

 

Mike

The Speed is GPS related so I think the lag is a millisecond....much the same as 12g was a millisecond....... I must look at the video again to see the cables.... now starting to think Kev was giving a lot more thought to this than just plonking it down wherever it happened.

 

 

Yes Pete, we all know you ... and like myself you can also talk about the plane that could not fly away after arriving

Kasper,

 

You have the advantage on me because I don't have a clue who you are ;-)

 

As to the reference to : " and like myself you can also talk about the plane that could not fly away after arriving " I am sure you are talking about a certain X-Air?

 

There is a saying " You can't make an omelette without breaking a few eggs " On that day I made a mess of said omelette....... not bad considering how many other omelettes have came out perfect ;-)