Hughes 300 Vs hughes 500 question

[bladepitch]

hi guys.

i was just asked a question for which im most eager to have answered.

as with tuna fishing boats , 500s are used and the question was posed why not use a 300. im sure they are used in some cases
the answer i was given was that the 300 suffers more from ground resonance on ships while the 500 does not suffer this.

1. is this true and why

2. does the numatic struts play a part on the ship worse than they would on land.

3. what would be the main reason (apart from turbine reliability and speed) that 500s are used

Cmon everyone chip in with you 2 bobs worth! especially lu and nick

Cheers BP

[toivonen]

Hi, we have tryed the 300 on boats but there are two main conserns,
1 there are no rotor brake (try to stop the main rotor withmore than 20 knots wind without rotor brake)

2 the 300 is under power'd for the demands in tuna fishing ie fuel load,radio buey,2 pax, fixed floats and temps around 30.C

[spinwing]

Bladepitch .....

Don't think Lu will be able to help you with this! :{

Where to start ....

1. 500 less maintenance intensive then the 300.
2. 500 M/R Blades easier to Remove/Refit when required.
3. 500 has Pop-Out float kit available .... Fixed floats on 300 & 500 are a pain to maintain aboard a ship.
4. Yes 500 much less prone to Ground Resonance then 300 though i understand 300 with Elastomeric lead/lag dampers are now much better.
5. 500 much better control response and more agile ... which makes deck landing in rough conditions much safer.
6. Tie down provisions on the 500 way better than the 300.

There is probably more ... but my head hurts ... time for a lie down! :zzz:

[Bravo73]

I'm sure that the relative cruise speeds (120kts vs 70kts) might also have some bearing on matters...! ;)

[bolkow]

Captain Jack Coustou whatshis name on the calypso used the hughes 300 to good effect but not slinging anything as far as I am aware

[Verbatim03]

Also Captain Steve Zissou used a Bell 47 on the Belafonte but I think they had some reliability issues.

[bladepitch]

[QUOTE]
Yes 500 much less prone to Ground Resonance then 300 though i understand 300 with Elastomeric lead/lag dampers are now much better.



Spin
can you elaborate a bit more as to the system that the 500 uses against the 300 and what part the numatic struts could play in this (if any)
ive had very little exposure to these aircraft!

cheers to all replys so far. keep opinions coming!

so about the lu comment. (didnt know lu had passed, its been a while since i was on here)

cheers BP

[spinwing]

BP

Both A/C have "Fully Articulated" rotors but he effective hinge offset on the (various) 500 heads makes it "fly" more like a "Rigid Rotor" type head ( the aircraft in fact flys very much like the Bo105) but perhaps smoother and much faster.

The 300 head has a lot of articulation to it and to keep this under control in the lead/lag sense the early 269 series a/c used hydraulic/friction dampers.
These dampers used to wear quite a bit ..... and as a result often one damper (of the 3) would be less effective .... this would lead to one blade moving out of phase in the disc ..... not always a big problem ..BUT if the a/c also had some slightly "saggy" pneumatic u/c dampers and the pilot was a bit rough either engaging the clutch on startup OR a bit ham fisted landing the machine it would go into "Ground Resonance". The level of resonance being a question of luck for the day!

Very often after a rotor start the a/c with a low lateral vibe we would pick the a/c up go to a grassed/soft area and carry out a hovering auto ...to re-phase the blade dampers and get everything back to its "as advertised state".

The 500 series a/c having either a 4 or 5 blade head of quite a different design (brilliant for its time) was almost impervious to the "Ground Resonance". Also the u/c dampers on the 500 were of a better design tended not too leak down and thus gave less problems to maintenance.

Cheers :ok:

[bladepitch]

cheers to all

catch ya round on the rumor mill.

BP (out of action for a few months)

[500 Fan]

Apologies for a Heli-Anorak question!

Is the Hughes/Schweizer 300 fitted with the exact same model of Air Cruiser fixed float as is fitted to the Hughes 500C? They look pretty similar but I have an inkling the H300 floats are a little bit smaller than the H500 floats.

Can anyone provide a measurement for the length of the H300 float? I can't find any measurements on the interweb. Thanks.

500 Fan.