View Full Version : AS350B2 , B206L4, B407 comparison
10th Nov 2003, 17:24
For you experienced operators with operational experience on AS350B2, 206L4 & B407, I would like to ask a simple question.
A friend of mine is looking to buy a corporate ship for his company use that say will carry 4-5 execs at a time and when not using the helo for company use would like it to be used for charter and air work duties by our organisation.
this particular person wants to know the best value for money, performance, in service support and reliability. He has decided on the final 3 helos above for his choice.
I have my particular views as to what his best option would be however i wanted to get some thoughts from all you out there who have had experience in these types.
Any discussions would be welcome
11th Nov 2003, 14:02
I have 350B2 and 407 experience, and have found the 407 to be slightly more powerful and has a slightly faster cruise speed, and a lot faster climb speed.
The split cabin is an issue, but on the plus side, the structure around that 407 rear cabin is tough, unlike the composite (read...plastic) hood covering the Astar cabin. The Astar is truly a crowd pleaser in the ride, noise level and comfort department otherwise.
Don't knock the 407 rear visibility and comfort until you have tried it, the windows are larger than the "L" series, plus the cabin is 7" wider.
I had the opportunity of chartering a VERY rich Austrailian family from a remote heli-Ski lodge to an international airport, they all sat in the rear of the 407 drinking champagne, go figure? Who needs a front seat to view the Canadian Rockies anyway?
As for operational cost, my company deems a 407 is actually cheaper to operate than their previous B2's.
Captain Lai Hai
11th Nov 2003, 14:37
I had the pleasure of doing a few hours longlining in the 407 on the fires earlier this year.
Very responsive solid feel absolutely loved it.
I thought the start procedure though was overly complicated compared to the French Fadec systems and I was concerned about the problems and consequences that could arise if they wern't correctly followed.
I know I may receive some negative responses to this but the french stuff seems to be more pilot proof.
Another problem was the temp limitation at around 1000' asl which another 407 also working in the area was also experiencing.
Both operators tried everthing to rectify the problems changing all the usual associated components etc without any success.
Our Lama's (originating from late 50's technology) lifting capabilities and reliabilty are significantly better than the 407 I flew
11th Nov 2003, 14:51
-watch the computer self-test horns, lights and instruments.
-fuel pumps on,
-throttle to idle,
With any computer system, procedures must be followed.
What is involved in a B3 or a Lama start for comparison?
Temp limited, Torque limited, or NG (N1) limited, the question remains, will it perform to Flight Manual published data?
Back in my 350 days, I recall that NG was the first limit reached after departing the base.
No question, about it Capt, a Lama will out do a 407 everywhere and anywhere...except cruise speed :ooh:
12th Nov 2003, 00:02
Hmmm!:confused: But doesn't it go awfully quiet shortly afterwards if you don't put the Fuel Valve ON?
12th Nov 2003, 00:43
I have flown the aircraft and of the three I prefer the A-star. For passenger comfort, noise,ease of entry/exit, and performance this is the best aircraft. Your personal preference will of course be the final deciding factor. For charter work the A-star , I think, gives you the most flexibility. For instance, take the doors off for photo-work, the large cabin area for internal cargo, and the choice of hooks for external load work.
Our company has operated all the aircraft in the past. We now have 18 of the A-stars and none of the others. The support has been an issue. Depending on your location, it may not be as difficult as you think.
All three are good reliable aircraft. Check performance numbers carefully at the loads and altitudes you will operate at. Think about your needs and how each will answer those needs. You can't go wrong with any of them.
12th Nov 2003, 01:19
My recommendation is limited as I have no 407 experience.
First the Bell contenders- They are a great but dated helicopter design. Mature, reliable and easy to fly within their limits. A bit less comfortable and agile than the 350. One large baggage compartment. Think "truck" that hovers- and hovers well.
The 350 on low skids is much easier to enter, quieter and comfortable as delivered from the factory. 3 smaller baggage compartments. From the pilots point view, much more room and comfortable to fly. A very adaptable airframe.
I think you'd find the L4 and 350B2 kitted out de luxe will have short legs, on the order of a half hour range and return with half hour reserve and 5 passenger seats filled. If this is acceptable, I'd pick the 350 over the L4 purely for pax considerations.
If unrefueled longer legs are an issue, the 407 might be worth investigating.
12th Nov 2003, 02:22
Comparison of the three is like Apples and Oranges. It also depends on the VIPS, other factors, Location, are you in Denver 5000' or Los Angeles
Having played with all those toys I think Bell has the best ship in the 407. Its really sweet when its got all the VIP stuff. Also having done tours. I dont think you want to mix a nice VIP ship with tourists. They are by nature overweight and treat your euipment like its a cattle car. For Tours and Tourists, Eurocopter has it best. You can do a lot ot one of those things without all the Bell, Bells and whistles going off.
Best to figure out exactly what you need and you will certainly find it between one of those aircraft. You might also through in the EC-130. When money is no object, folks dont object to spending it......
12th Nov 2003, 05:53
Sandy Toad, If we really want to get picky...we as pilots complete a pre-flight or pre start checklist on each and every type that we fly, either in printed form or from memory. You are correct, the fuel valve must be on, the FADEC must be in Auto mode, the the fuel quantity must be checked, the doors must be secured, the passengers briefed, the instruments and switch positions checked, etc, etc, etc.
I humbly apologise for forgetting to mention such an important switch.
My "reworded" point is that when the normal prestart checks are completed, the actual start sequence is fairly simple.
I'd like to compare it to a Lama or B3 start sequence.
12th Nov 2003, 06:11
Thanks for all your comments and experiences reagrding these machines.
Our company operates pretty much at sea level here in Oz as we are located on the coast, our out landing wouldnt go much further than 6500' here and thats down on the ski slopes!
We operate Bell machinery but i have some time in an A-star and have found it a very pleasant machine to fly.
Our corporate friends love the idea of the open cabin layout of the 350, however EC support seems to be lagging behind Bell at the moment.
Ultimately it is our clients choice as the machine they purchase. and i was curious as to your ideas on these types.
Ive yet to step out of the good old manual 206 start and Having only flown an EC120 with the new digital cockpit layout and getting used to the FL Indicator which is not hard mind you! I have had no experience with FADEC.
I have watched starts in an 350B3 and it looks quite if not to simple to start, on the B3 what position is the throttle positioned during the start and at flight, what are the procedures for a fadec failure and then reverting to pilot controlled throttle?. Is the 407 start a similair procedure?
12th Nov 2003, 07:05
The 407 start sequence (after preflight checks :O ) is posted above.
The latest 407 software update (5.202) has direct reversion to manual mode.
Captain Lai Hai
12th Nov 2003, 10:16
407 Driver greetings
Information as requested abreviated.
I seem to recall that there was either someting about the start or shutdown with the 407 that could cause some problems if not followed correctly.
Lama Start procedure
1.Fuel flow lever back (closed)
4.Boost pump on
5.Start switch on (up position)
6.Monitor start lights illumination and sequence
7.green light on
8.amber light on
9.amber light off
10.green light off indicates 870 horses ready to kick ass after clutch engagement (chapter2)
11.If the red light comes on abort start and vent by returning start switch to center position momentarily then down to vent position.
For the AS355N Fadec
1. 3 x Batt switches on(2xmain 1x direct)
2. Approx 10 secs computer self diagnostic check
3.select boost pump and gen for applicable engine
4.Start switch to FLT position monitor T4
5. step number 3 for second engine
6.The hardest thing about flying the 355N is staying awake.
I only ever had to abort one start in nearly 4 years due to a very srong tail wind on the number 2 engine.
12th Nov 2003, 10:48
Thanks for the info you posted.
One more question, when and Where is the throttle placed during starts on these types?
You are correct about the 407 Capt. LH
On shutdown, If you turn off boost pump pressure before NG reaches "0", the fuel metering piston in the HMU may not seat in the proper place. You WILL get a "start degrade" light on your next power-up, and will be required to go through a piston-parking procedure. It's simple, but a bit embarassing in front of customers and coworkers.
It's always good to sit in the pilots seat and monitor all parameters as the engine winds down anyway, right?
The 407 FADEC logic will handle most overtemp situations, and will automatically abort fuel-flow, while continuing to motor the engine.
We have had some hot and high start problems, the main contributing factors being:
-very high, 9,000 to 10,000 + AND OAT above 15C
-excessive residual MGT (TOT) mainly from a very short time after shut-down.
-Poor battery condition (24V min to start)
-a downwind condition.
With experience, all factors can be managed. ie, if you're working that high, plan on idling if the shutdown period may be short, or if shutting down at altitude, take a 30 minute break, always park into wind, keep a fresh battery installed...
10th Dec 2003, 22:11
So with all the posted info - Which of the choices did you choose as the best of the bunch? When questions are asked as to which is the best choice then before the topic dies we would like to know the answer.
11th Dec 2003, 07:40
B-3 Squirrel. Low skids, a/c, leather.
Comfort. high cruise speed, lift performance and looks. No other choice.
11th Dec 2003, 22:51
GROSSER - you are almost correct but I'd go for high skids every time. Read the CAA Tail Rotor Failure link. TR strikes are major cause of accidents and the added height with high skids is 'nice to have'
11th Dec 2003, 23:40
Maybe a bit off topic, but must agree with cap L.H. I've been flying AS 355N for several years and only problem in the start is if you're down wind, but out of that, it is really easy and ready to go in less than 1.5 min since you hit the first BAT switch. To me that is easy and fast
12th Dec 2003, 19:45
You never get something for nothing....
On the skids the B3 is the same as the B2.....but yet on the hook its worth a heap more, in fact around 550 kgs more.
Now put on your thinking cap and question what will happen when you put an extra 550 kgs on a system designed for 550 kgs less [2250 kgs MTOW]??
Of course, short turn gain but at a huge price....if you have yet to see the wear and cracks, then just wait.
The B407 is a nicer machine, but try and squeeze some big guys with a boot load of baggage...and it won't fit.
But the Bell service still trashes the Eurocopter arrogance.
13th Dec 2003, 11:04
our clients are looking at the L4 at the moment, ease of maintenance,adequite capacity and power for the corporate world and in service support seem to get the thumbs up.
i will keep you posted
14th Dec 2003, 18:20
The notion of the B3 having an overloaded structure is not an issue.
If I recall my studies correctly, the 2250 Kg internal MTOW of the B2 and B3 isn't a structural limitation but is rather a control limit for "the average pilot sans hydraulics". The B3 has a more robust MGB than the B2 and a different build spec for the MRB's. The hook is different too, plus lots of other bits. The structure itself is just fine at the B3's external MTOW (plus a bit).
It's kinda like saying the 407 is just a jazzed-up 206 so be careful not to exceed the 206's loads. The 407 does have the odd difference to its predecessor and it also seems to be handling its tasks OK. Not that I'd want one myself though.