JerzyGeorge

Bottom nozzle of my Savannah water radiator developed minor leak and on closer inspection I found hairline fracture where it was welded onto body of the radiator.

Is the installation of the radiator ( hung on rubber hoses only ) a contributing factor?

Any ideas on radiator installations.

On other aircrafts I have seen it bolted on brackets , not relying on rubber hoses only.

Thanks for any advice

George

The only evidence I've ever seen of what dead flyers think was in this film:

 

Hi All,

Can you recommend reliable tyre pressure monitor which works in flight?

I looked at some TPM available on the market but I think they work ONLY when tyre is rotating which obviously is no good in flight, when I want to know before landing that I have a soft or flat tyre.

George

Hi Guys,

Thank you All for interesting discussion,

Just to clarify my reason of full flaps:

I do it only when want get of the ground quickly ( soft , long grass, wet boggy). I figured out that it starts flying at lower air speed over the wings. With my 100 HP up front there is apple power to overcome rolling resistance quickly, unless I have a flat tyre just before take off. As soon as I am off the ground and have enough speed I close flaps and climb away. This allows me to get airborne with short ground roll and good climbing performance.

George

will have a look at mine tomorrow, though im not a fan of using full flap for take off though.

Of course my trusty Savannah VG

Of course my trusty Savannah VG

Hi All ,

Not long ago I had my flaps disengaged from full position to nothing during take off.

Not nice experience , but I recovered with no damage at all .

After thorough examination this is what I discovered:

1. The top bolt which is the lock-in bolt did not go into position - even with spring action .

2. I thought that flaps were locked , but as soon as I got enough air flow over the wing they slammed shut,

3. The problem is and please check your flaps assembly for:

a) the bottom bolt should work as a stop bolt in full flaps position

b) the top bolt should have a 1 mm clearance from the notch to allow for free movement

In my case it was opposite the top bolt was working as a stop bolt and not allowing to move up because of the friction. It is something hard to detect without actually looking down there or running your fingers there ( risking nasty pinch) because on the top of the flap lever it looks OK.

I do not use full flaps very often and did not notice this problem before ( having about 500 hrs.)

I used needle file to open 1 mm gap for the top bolt to allow it to slide free with the bottom bolt taking full pressure. Operated on the ground about 15 times and could not fault it.

I am sorry about the poor quality of the photo

George

Yes I agree, well spotted. I have different on my plane, not so pretty but functional they are flatter and supported from underneth from exhaust pipe which is directly under the carburator. This the whole idea to shield carby from hot pipe and possible fuel leak catchment.

Hi Rick ,

I think sometime ago you asked me about under carburettors trays , I have found a photo of the good one . Please have a look , I believe you similar not exactly same as accessories from Rotax but a bit expensive.

Hi Rich,

This has happened in Tasmania, it looks to me like slopy tanker driver left a bit of diesel in the "empty" tank or in the fuel lines.

Some people do not appreciate how important is to keep fuel clean. Disapointing that it happened to expensive 98.

you are right such a small contamination is not possible to detect visually.

Regards

George

Thanks guys for valuable comments, specially the one pointing out a chance of having test tube full of water without any petrol in it.

I avoid refuelling in wet or foggy weather, try to do it only when is dry and sunny, sometimes a bit of mission in Tasmania.

Jerzy my brain isn't working particularly sharp tonight so I was wondering if you could elaborate a little for me.Was the diesel in the oil? Or did the petrol have diesel in it?

 

As a side note we had a small engine stop on us the other day and when I drained the carby all I got was water, so I drained the tank and got over a cupful of water out of it as well. I couldn't work it out for ages but it finally clicked when I drained the jerry can into a clear jug and had 4 litres of fuel and 1 litre of water, I had been using that jerry can for the mower at home and I always leave the lids a little loose to prevent the build up of pressure and it just so happened that the kids had been playing with the garden hose so after a gentle questioning session it was revealed they helped daddy by filling up his fuel container with water:doh: so anyway they got their first introduction to small engine maintenance (gently of course!) and they now understand that water isn't quite the same as fuel:thumb up: so hopefully that won't be a repeated problem.

The fuel came from local service station and owner sent sample for testing. The results should be available next week , for a time being this particular tank is locked out.

I would like to share fuel contamination problem I did learn about yesterday.

One diligent pilot noticed oil level going up !!

And it was real no imagination.

Subsequent investigation pointed it out to fuel contamination by diesel fuel.

The same was observed in petrol driven cars using fuel from the same bowser.

So not only low oil level is a problem .

I need some advice how to fit long range tanks into my Savannah VG.

Some say that I have to take the wings off to do it , others that it is possible to do it with the wings on the plane. Also that fuel taps before lines get to the header tank are a must . What about additional weight (stress) further away from from the fuselage . Or is it too much trouble? Thanks in advance

Hi Jerzy,Have a look at my thread http://www.recreationalflying.com/threads/fuel-ambient-temp.142031/

Your snag may be due to other factors (as suggested by other responses)....but I have certainly seen high temps leading to dropping fuel pressure & increased fuel flow.

 

With us at no time did the 912ULS cough or show any signs of being unhappy BUT at 300ft doing anti-poaching work, watching one's fuel pressure drop and fuel flow increase sure gets one's attention !!!!

 

In our case its was / is definitely ambient temp with a few other factors thrown in. Our thoughts on the matter are that:

 

1. MAKE SURE your lagging on the exhaust manifolds and pipes are adequate and intact.

 

2. Make sure you don't have any leaking welds on your exhaust system....we had 4 small holes at various points, hidden by lagging. VERY scary

 

3. We are considering drip trays / heat shields (see http://contrails.free.fr/temp/912_installation_3.pdf)

 

4. If ambient temps are going to be high then AVGAS is the way to go.

 

5. Set limits on temp above which we don't fly .....not due to density altitude / PA issues but rather because the fuel system is not happy.

 

Hope this helps,

 

Rich

Jerzy

Thanks guys,

My electric pump is in the engine compartment but on the fire wall, the engine pump is at the front on Rotax and fuel lines run on the top of engine where can get hot , filter is before pumps just on the outlet from header tank , inspected every week. So I reckon I will get the fuel line thermals on the lines to engine pump.

Thanks a lot Nev,

Bolts are tight, checked them as checking others, all the connection on fuel lines tight, but do not have red thermal insulation on fuel lines. It runs on mogas 98 UL Jerzy

I have another question:

About 2.5 years ago on taxing back to hangar I noticed fuel pressure fluctuating widely . It was very hot summer day in NSW , Changed the engine pump for new one and never happened again even in hot weather.

Until yesterday , While flying about 3,500 feet and filter air box temperature about 30 deg C I noticed fuel pressure dropping slowly. Was not happy at all , switched on electric pump , pressure came back where usually is on engine pump only. After short time I switched electric off and pressure started dropping again , was not brave enough to wait and see how far will drop. Turned electric on and was good . It happened a few times with time in between anything 10-15 minutes. In the end left my electric on for a duration of the flight 1.5 hours. I am thinking of replacing the engine pump with the new one again.

Any comments from you guys?? I cannot provide any numbers because my pressure is only indicated by green field with no numbers , but I know where usually is or where should be.

I am pleased to confirm that everything has been checked twice all nuts and bolts including engine . Have not found any problems, found cabin roof panels where wings skin is jointed a bit flexible there , more on the left side , and this noise was put into this under certain air flow during side slip. Took it for a flight and could not fault it , did a gentle side slip and no noise , but wind was more steady this time and side slip no so agressive.

Thank you guys for all useful comments.

HelloI bought a Savannah Xl one month ago and I am very happy with it unless for the nose wheel vibration (I posted it in this forum).

 

I never had a STOL plane before, I flew a Tecnam Sierra for 5 years and a Cirrus SR-20 for 7 years. Now I have to learn to fly slower and sometimes it is not easy, I made 4 hours with an instructor, the speed approach I used it is about 50-55 mph and in the threshold I try to reduce to 45 mph. My instructor landed the plane with the nose very high holding the stick in the chest to settle the nose wheel very slow, this look like a perfect landing but I felt with this way it is very easy to make a balloon in the runway and I can´t even see the runway , I am used to land more plane and not to hold back the stick so aggressively. I noticed too if I approach hight it is not easy to get the correct path with full flaps neither with a slide, I feel the plane float a lot, maybe I am used to a airplane like the Cirrus with very effective flaps and very heavy, and it makes very easy to low descend very quickly.

 

¿Is this way and the speed I use the best way to land the Savannah? In the manual I saw with full flaps you can approach slower (40 Mph) but I think it is very slow speed and I would feel uncomfortable flying at this speed.

 

Could you tell me what´s the best way to land the Savannah to take advantage its STOL capacity .

 

I think I land quicker than I should and maybe I use a wrong technique because sometimes in sand runways the plane skid when I put the brakes an it could be dangerous.

 

I think I must get used to fly a Stol plane and to practique more the slow flight because when you come from quicker aircrafts it is not easy to fly so slow.

I have c.a. 500 hours and many landings on it and always try to keep my speed 40-35 knots on approach with 1-st stage flaps. Not very often I use full flaps and speed is 35 knots . Looking at the videos above I am pretty sure that it was not far from stalling. When I fly I like to have a margin and always ready to full throttle and go around. You can execute pretty hard landing on Savannah as well. On rough strips I land on main wheels with nose only slightly up to take the weight off it .

And be very careful with hard braking because it will put a lot of load on front suspension. When flying very slow always hold it with the throttle do not glide only. And when going around keep an eye on max full flaps speed.

One of the good exercise is to fly a meter or less above runway at the beginning at 40 knots and then gradually lower your speed 5, 10 knots and have plenty practise on long grass runway , get the aircraft to react to your stick and throttle actions.

Do not touch down front wheel first because cannot take a lot of abuse. It looks like you are experienced pilot and have more hours than me , so sorry to say all that.

HelloAfter flying 10 hours my new Savannah XL I am very happy with it but I have one concern about the brakes:

 

I have noticed in some sand runways I have skidded to the left and right after I pushed the feet brakes I think not very strong and not very quick (30-40 mph aprox), I was a little concerned about this because I felt I could have gone out of the runway, I suppose these feet brakes are very powerful if you compare with the hand brakes most of the ultralights usually have. I suspect I need to use them more softly, anyway I have always used the brakes hard in all my planes and I have never skidded a plane before.

 

I think the Savannah has to be nearly stopped to push the brakes in a sand runway but I see it a problem in a short runway If I can´t use the brakes from the first moment I am rolling over the runway.

 

I´ve thinking to change the feet brakes to a hand device to brake to both wheels and not differential brakes like the Savannah has.

 

Now I am a little afraid to push the brakes in a sand runway and I try to wait until the plane is nearly stopped but this way to land I don´t like when the runway is short.

 

¿Do you have some advice?, ¿Am I doing something wrong?, ¿has anybody had the same problem?

 

Regards

 

Carlos

Differential brakes are wonderful, I have 500 hours on Savannah and would not change to hand brakes.

Make sure that you have even tyre pressure on main wheels. And landing on soft sand. wet grass or loose gravel it is possible that one wheel or the other will present higher rolling resistance , happened to me a few times and this is the moment when differential brakes are worth gold you can straighten rolling direction with your feet activating brakes like tap dancing or ABS in your car . Have to be pretty quick with your feet and do not wait fully for the results , do not overdo it . the best way is to practice on grass strip in lower speed and get the feel for it. I have fairly large rudder pedals ( like a drilled aluminium pedals for race car) with toe brakes on the top. My advice is do not convert to hand brake learn how to take advantage of toe brakes, keep tyre pressure the same ( left=right). Happy flying

Thanks a lot for quality information , had a look at the photos and will check those bolts on mine. I was changing spark plugs over the weekend and did not notice anything missing , but will double check.

Jerzy

This. I had a similar noise in an Allegro while side-slipping (not on purpose - I was new to type and couldn't keep it in balanced flight!). If I side-slipped on purpose, the bubble doors would pop from convex to concave - who needs a skid ball :-)The popping noise I got was from skins on the tail, which, if you pushed on them would also go concave - making a scary noise in the process!

 

Wander about pushing on the skins, and see which ones 'pop'.

 

Mal.

Any opinion and recommendations , I am thinking about Trig 21 but it is a bit expensive I fly close to CTA quite often and think would be usefull and also traffic avoidance system in other aircrafts will pick me up.