Robin DR401 as an IFR tourer

Is it permitted to fly in IMC conditions? On the website I only seem to see VFR (day + night)

I think you need to widen your browser window :)

A number of those above seem to be doubtful of wooden construction for aircraft and I think it is worth remembering that the best light bomber of World War Two was built of wood, these aircraft operated in all sorts of weather and a general operating environment far worse than any light aircraft. Wood has some disadvantages largely around being left in very humid conditions, the Mosquito had problems in the Far East and I have seen a Robin that was left outside in the Far East for two years that rotted so badly that you could put your fist through the main spar. How ever these are extreme situations that most of us are unlikely to encounter.

My 1974 Robin is currently having a major rebuild and has had very little renovation of the wood structure, the only area that required more than light work was the fuselage area that sits on the wing, this is due to the old type of wing / fuselage seal that funnelled moisture into the joint, this has now been superseded by another type of seal on later aircraft, I don’t expect the aircraft to need any major structural work for the next 25 years once the work is completed.

The aircraft is a very capable touring aircraft and capable of IMC flight, just how much hard IMC the aircraft is capable of without an autopilot is down to what the pilot is happy with, I have flown the aircraft for 3 hour legs in hard IMC without any automatics without problems.

In terms of aircraft performance & payload the DR400-180 is between the Piper PA-28-181 and the Piper PA-28-201 Arrow ( non turbo ) but the DR400-180 can do this off of a grass runway 30% shorter.

Overall there is no better fixed gear fixed pitch prop four seat aircraft in terms of cost Vs performance, the DR400 must be be kept inside but over the long term any aircraft kept outside in the UK will cost in corrosion & Avionic repairs as much as is saved in hangarage fees.

I have yet to fly the diesel engined DR400 but suspect that it is likely to be a very good aircraft for most private users with the DR400-180 having the edge for those who’s mission is high payload or long range.

DR400 must be be kept inside

What if the hangar has no doors, like the two main ones currently at Shoreham?

Peter

It is humidity that kills wood structures, my first DR400 lived in a what was described as an implement shed that was open at one end.
The constant breeze through the shed resulted in a dry atmosphere, I would be far more concerned about keeping a DR400 in a damp hanger with next to no ventilation.

My feeling is that a DR400 kept in a dry atmosphere, regularly flown and with care taken with maintenance of the paintwork would last twenty-five to thirty years before major structural inspection would be required, even at that point you are in my experience unlikely to find any problems that are safely critical but the 25/30 year point is the time that is most economic to prevent small issues becoming major ones.

As to the doorless hangar at Shoreham my worry would be the salt laden atmosphere corroding the metal parts, the DR400 has minor issues with corrosion on the light alloy parts most of these are not too much trouble to replace. It would be metal aircraft that would be of most concern to me and if I was a metal aircraft owner I would be making sure that the airframe was regularly treated with CorosionX, LPS or one of the other avalable anti corrosion compounds.

Re indoor/outdoor debate… When I was at the factory I discussed this with the owner of the company who very much supported what A&C says above -he said that he’s seen Robins live outside eg at flying schools for many many years, as long as they are flown regularly the wing dries out quickly, whereas he’s also seen rot set in on a hangar queen kept (but seldom flown) in an unventilated hangar.

His feeling was that living on grass all year round in a damp country was tempting fate, but hard standing no problem, especially if a poly tunnel or similar protects from sun and storms – the main criteria was to fly the plane, then the storage conditions were not a critical factor. In summary he was very clear that the dr400 can live outdoors and our doorless hangars at Shoreham are no problem – except for the birds!

I DO agree that some of the exposed metalwork is a bit vulnerable to sea air and would be better in stainless – just a few hinges etc. I may replace these over time.

“the 25/30 year point is the time that is most economic to prevent small issues becoming major ones”
Based on my experience as an owner of a 1972 Jodel Regent I would debate this 25 or even 30 year age as a landmark for a major inspection. It all depends on how a particular plane was used and stored.
My bird was 42 years old when
purchased and from aesthetic point of view was far from perfect. The very complete overhaul of the airframe, down to a smallest screw revealed one, just own element which needed to be repaired: the doorstep below baggage compartment door.
Frankly, I don’t see any reason why a new Robin, especially one covered with Oratex would serve you less then 40 years without a major overhaul.

Humidity is a very big problem in metal aircraft, too, and neglected storage outside isn’t good for FRP-planes either.

As an example this is a spar cap of a MS893 stored outside and unflown for just over one year in eastern Germany.

With “modern” wood treatment there is no reason to believe wood would be inferior to other aircraft building materials, especially in small and light aircraft. There is a nice piece on the history for the domination of metal aircraft here: https://www.jstor.org/stable/3106748?seq=1#page_scan_tab_contents -

If you buy a DR401 (or recovering a wooden aircraft), you likely want to have it covered with Oratex for good protection, strength and repairablilty (there is even certified Oratex speed-tape to make field repairs easy). Our Capitaine and my Ka1 will be covered with Oratex, no doubt.

I agree, but I don’t think the above is from just one year. More like 10-20 years and a negligent maintenance company.

This has been discovered in Socata TB elevators – some really spectacular photos have been posted online, and IIRC I posted some here with the owner’s permission – and seems to be caused by people tying the controls back with an elastic band, instead of locking them neutrally with the yoke lock which would allow the drain holes to work.

The wood in wooden planes is not going to corrode but there is metal too. I hear from a DA40/42 maintenance engineer that the annual bill for replacing corroded metalwork on these types is very significant. Cadmium has been outlawed (except in aviation and military) and it doesn’t look like the plating on these is very good.