Enstrom Corner

[Flight Safety]

GB, I wanted to add the following two points.

First, Enstrom released a newly redesigned main rotor drive shaft that has a thicker wall, which cured the previous track and balance problems. I understand that new machines come with this shaft, and it can be fitted on older machines. Maybe you can find a ship that has this new rotor shaft installed.

Second, maintenance on an Enstrom can be a little tricky, as some of the procedures (drive alignment procedures in particular) are very precise. If you're thinking of buying one, be sure a good maintenance shop is located nearby, staffed with folks who know what they're doing with Enstroms.

[Gaseous]

I've got a 1975 F28A which I have had a couple of years. I love it.

What kills Enstroms is water. ALL the bearings in mine were shot due to water ingress and corrosion. Lamiflexes in the UK are 5 year items (unless this has changed recently) and are expensive. $1000 ish each. Tracking is not a problem provided the rotor head is in good condition and the blades are reasonably matched. most older aircraft seem to have a random assortment of blades so if it won't track a blade swap may be the answer. Used blades are cheap and available and unlifed. Dampers can be a problem but mine were fixed and are now perfect. After a thorough refurbishment it is pretty reliable with no significant faults this year and only a failed starter last year. It is slow with cruise at 80 mph (not knots) and certainly not overpowered but provided kept under max weight is not a problem at low level in UK summer. I installed a graphic engine monitor and balanced fuel injectors so it will run according to John Deakins principles - well lean of peak - and at that burns around 8 imperial galls per hour and is cool and clean. Not that I do of course as the POH says mixture full rich at all times. .

Hot starts are not too bad althought the POH method is not the best in my experience.
It can be trimmed to fly hands off and can be steered by simply leaning in the seat. I do not find the controls in the least heavy. Anyone buying an old one should be prepared to spend a lot of time and money to make it right. When that is done it will be a cheap,safe helicopter.

[Billywizz]

to MD 600 driver,

Lots over here??? there are only three schools to my knowledge in the UK that train on them and there aren't that many about, last I heard there were only about 23 in the country. 480 was nice to fly but the rest were uncomfortable and hard work on the old biceps.

[Vfrpilotpb]

Hey Billy Whizz,

Up here in Lanky we have Barton Helis they use em, and sell em, if it was nearer to me that EGNH I would have started on Enstroms not R22's, been in a couple of Enstroms and find them far more stable and slightly quieter than the R22 and just as flyable, although never out in any bad wx with one, quiet a few people who own them are in the locality and seem to enjoy them
Peter R-B
Vfr

[Gaseous]

Billy,

There are 76 on the UK register in varying states of airworthiness. There seems to be a bit of a revival going on at the moment . I know of a couple of dead ones being restored. People are realising that they are actually quite good when restored. Most of the UK fleet is ancient and they got a bad name as a lot were left out and neglected which is a recipe for trouble and expense. (If you go to Barton there are usually 6 or more standing in the rain - and it will be raining)

If you have any doubts about what they will do, just watch Dennis Kenyon in a 21 year old F28.

Peter, In bad WX they are much, much more stable than an R22.

Give me a good Enstrom F28 rather than a R22 anyday.

[The Nr Fairy]

Check the blades carefully - you may find one which has not been back to an approved shop for repair after delamination. I hope it's been destroyed by now . . .

[Gaseous]

Nr Fairy,
There are lots of repared blades out there, and field repairs under 3 inches long are allowed according to my engineer. I don't have any repairs on my blades now although when I got the helicopter it had just passed a C of A with a large, very obvious trailing edge repair. That blade has now been scrapped. I have experienced a large delamination in flight. It caused moderate vibration but only when the lever was lowered. Blades are lifed 'on condition'.

[CountryMember]

I had an F28A followed by an F280C. Both machines were great to fly although the uncorrolated throttle made an overspeed easy. The big problem with the Enstrom was the maintenence costs. I was told that I could run an H500 for what my Enstrom was costing me.

I then bought an H500C and after 15 years they were right, the costs were about the same and obviously there was no comparison on the performance of the 2 machines.

The Enstrom is a safe crashworthy machine that has no time life limitations, but I think engineering and perfomance wise the R22 and R44 are supierior.

[md 600 driver]

you must have had a very poor enstrom and a exeptional 500
but if it worked out for you thats great


regards steve
do i know you

[Ga. Chopper]

It needs 29" MAP just to hold level flight, so if the turbocharger quits you are out of the sky, even with the rest of the engine working.

That may be true if hovering at higher gross weights with calm winds and hot outside temperatures, but that is not true for forward flight at speeds above ETL. If the turbo fails in a hover or prior to accelerating thru ETL, the ship would slowy settle to the ground. With full fuel and two people onboard, I can set 23" to 25" MAP and easily do a "run-on" takeoff, be airborne once thru ETL and climbout conservatively.

I normally use 28" to 29" MAP in forward flight for a cruise power setting which yeilds about 95 MPH, that's only about 1" to 2" of boost above ambient.

In the traffic pattern or for slower flight, I set about 23'"to 25" MAP which yeilds about 70 to 80 MPH. No turbocharger required at these power settings, it's operating just as a normally aspirated engine does without any turbo-boost at all.

For a desent or approach I set about 18" MAP which yeilds about 70 MPH with a descent rate of 500 fpm.

Bottom line: if the turbo quits, the ship "WILL NOT fall out of the sky! But transitioning back into a hover prior to landing will have to be accomplished quickly or a run-on landing at low airspeed will also work fine. I frequently practice this non-normal procedure just in case and it is no big deal at all.

it was a mongrel to start when it was hot

Sounds like there may have been a problem with the fuel servo/idle mixture settings or an improper starting procedure may have been used. If any of the "foil" wrapping was missing from the fuel lines it will cause vapor lock to occur during a hot engine start procedure. I have shut mine down and re-started it repeatingly when it's hot without any glitches, such as when I have tracked the rotors system or refueled.

I didn't like the F28C, but the 280FX is a pretty nice ship to fly.

Sounds like something was wrong with the F28C you flew, the F28C flies much the same as the 280FX; other than it has 20 less horsepower and more drag due to the wider cabin. Since all piston model Enstroms use the same rotor/drive systems, they all fly pretty much the same. The only major component difference between the two piston models is the forward cabin section. If you compare a F28C to a 280C or a F28F to a 280 FX, (apples to apples comparision), you will see they fly almost the same except for a small difference in top speed, (5 mph), due to the difference in frontal area drag. Also due to the lower drag of the cabin, the 280C Shark and 280 FX will glide a little better during decents or autorotations. Even the 480B tubine flies vey similar the piston models and uses many of the same parts in it's rotor/drive systems.

Furthermore, the transmission was made from an old Chevy (I think) and the design hasn't changed much.

This is not true! Externally, it may "looK" like half of the rear end differenitial out of a large truck, but in no way does it resemble or operate like any automotive transmission. This is not an experiemental aircraft, the FAA would not certify a design like that. Besides, the structural loads, gearing ratios and torque would not work in this application. It is amusing how many myths are floating around out there!

Most of the other problems (i.e. lamiflex bearings, tracking, etc.) have been resolved over the years. I have not experienced any of the issues or problems that some of the others have posted here. I am not affiliated with Enstrom in any capacity, other than as an owner-operator, and as a factory trained/certified mechanic. I have owned my F28 for almost 5 years, have flown several hundred hours in it, it has been provided me with safe and reliable operation.

The maintainence is similar to a Schweizer which is not as good as the Robinsons. But I think the Enstrom is better in most of the other areas of flying, especially safety. If you check the NTSB accident and fatality statistics, you will find it is the safest in it's class.

As far as the controls feeling heavy, that goes away after several hours of learning how to properly use the trim, then it becomes rock solid with hands off stability! I can also take my hand off the collective in forward flight and not touch it again untill it's time to change the power setting for the approach and landing.

I got my Private pilot add-on in the R-22 and think it's a great trainer. It is more econonmical to operate and has been great for the flight schools. Since then, I have received the Commercial add-on rating in my Enstrom and should soon have the CFI add-on as well. All the various types of Autorotations in the Enstrom are very safe and easy. These excellent flight characteristics have vastly improved my skills and confidence.

I feel safer in an Enstrom than in an R-22, but the R-44 Raven is the only other piston helicopter that I would feel just as safe in.

[Amazon man]

Enstrom F28 share

I am considering purchasing an F28/F28 Shark helicopter with the intention of completing my PPL/H and then building hours towards a CPL/H.

Is their anybody who would be interested in taking a half share or perhaps third share in a helicopter to be based in Hampshire somebody with land or hangerage would be especially welcome.

Alternatively is their anybody already owning an Enstrom in the South UK who is considering offering shares.

Many thanks

Please no comments with reference to pros and cons of Enstrom i've done my research and am quite happy with my choice.

[jerry712731]

UK Enstrom Conversion

Where can I get an Enstrom F28F conversion done in the south of England ?
I have looked through the relevant CAA documents and it seems to be a very rare aircraft listed by TRTOs.
Only one organisation seems to be current and they are not in the south
Any ideas would be welcome

[outofwhack]

Blade delamination

Pls forgive a first posting from an Enstrom owner wannabe.

I'd really like to know what to look for when purchasing a Enstrom. I have in mind a low houred 72/73 F28A. Comments please.

Questions in my mind are:

Is the big gotcha blade delamination?

I always thought delamination was a fault of laminated structures but aren't Enstrom blades all metal? Where are the laminations?

If delamination occurs what does it look like, how much can be tolerated and how much are new replacement blades and are there options to get hold of low time used blades for southern hemisphere use

[Vfrpilotpb]

Good morning OOW


Why are you asking about Delam, when by your own admission you dont know what it is, the only sound advice I would suggest is to seek out the service of a good engineer.

If you are just asking then it is very difficult for anyone to give youi sufficient information by reading here on this thread, the engineer is THE ONLY SAFE ROUTE.

IF HAVE ANY DOUBT'S about your Enstrom PLEASE do not fly it until it is checked out

WE do not want to read about any accident with any helicopter if it can be avoided

Peter R-B

Vfrpilotpb

[outofwhack]

Pardon me VFRpilotpb

Do you always bite the heads off newbies? How patronising!

I never said I dont know what delamination is and I didnt say I owned an Enstrom. I do know what it is [from many years with composite fixed wing aircraft] and I am merely looking around for a good second hand helicopter [and Enstroms appear to technically outclass other types in their class].

I'd really like to learn as much as I can so that I can spot a good one.

Certain people on PPRUNE always seem to assume their fellow aviators are stupid.

You suggest an engineer is the only safe route.
When considering buying a house you dont need a licenced engineer to spot if it is falling down. You simply dont buy the house. Do you also suggest paying 200 quid for a building inspectors report before you do your first recce.
You pay the licenced engineer for his professional opinion when you have done your own homework and satisfied yourself and before you have paid over the dosh.

I am looking for useful advice rather than the _____ obvious.

Like telltale signs of delamination on particaulr types.
How long you've got when its spotted?
How much, if any, is tolerated?

OOW

[Aesir]

I´m not a mechanic however I learned that if you suspect blade delamination a quick check could be done by doing a "tap" test, using a US quarter (25 cent) and knocking the blade listening for hollow sound!

In regard to you asking about metal blades and why delamination applies I suspect that the blades are glued together in the same way as R-22 blades and therefore subject to delamination.

May I also suggest that you look at H-300 and R-22 if you are looking for a piston helicopter, both very reliable.

[Maverick Laddie]

Aesir :

I do hope that 25 cent piece you recommend in your check for delamination has been calibrated. !!!

[ShyTorque]

Does a 25 cent piece work on european helicopter blades - or must one use euros? They are right-hand thread, of course.

[Vfrpilotpb]

Good Afternoon OOW


I am sorry if you think I have bitten off your head, or I was being patronising, I was trying to impart into your mind the acute seriousness of what you were asking about.

Obviously you already know the answer to the question you pose, by the way you phrased your reply in your second post, plus you have jumped in on full red alert .

Remember always, Helicopters are totally different than FW craft, and will bite the entire body of any unwary pilot be they high time or low time .

I stick with what I said earlier, If you are going to buy any used helicopter,or you already have one off your mate, it should have a full service history and be checked by a fully competant engineer. if that sort of comment winds you up again, well then what can we say!

PeterR-B

Vfr

[Flingwing207]

And they wonder why so many helicopter pilots are alcoholics...

This is a generic response - with 5.4 and four preflights in a 280C, I don't claim to be an expert on that particular aircraft.

The blades delaminate at the trailing edge, where the metal is bonded. They can also delam at the root. While the delam itself isn't usually immediately critical, the problem is first: corrosion - water gets into the blade, and sooner or later weakens the structure sufficiently to cause failure. The water can also enlarge the delam, especially in winter if it freezes.

The second problem is that the delam changes the aerodynamics of the blade. Of course this problem could also be a blessing in disguise, as it provides a possible warning - vibration due to an out-of-track blade.

The aforementioned "tap test" can help find a delam, but is in no way guaranteed to. The best way that I know of is to be fairly religious about cleaning the blades (with a non-corrosive cleaner of course), and visually inspecting them. Any new rotor vibration is to be taken very seriously! If you have the patience, use a magnifying glass to inspect (say every X hours in service).

Finally, as was previously suggested, start your ownership by having the blades inspected by an A&P who is well versed in the Enstrom, and be sure you have the accurate history of the blades. Since they have no TIS limitations, it behooves you to know "where those blades have been"!