Deep survey
HALVARD-9
Six kilometres down, running a survey line for forty hours without asking anything of the surface.
- Depth rating
- 6,000 m
- Line accuracy
- ± 9 cm
- Endurance
- 40 h
Fleet 03
Each class exists because a client asked a question the other two could not answer. Nothing here is a variant of something else, and nothing is listed that is not currently in service.
- Classes
- 3
- Hulls in service
- 21
- Deepest rating
- 6,000 m
- Longest deployment
- 90 d
In service, four hulls
Long endurance
DRIFTER
Ninety days on station, moving on buoyancy alone, reporting only when it has something worth saying.
- Endurance
- 90 d
- Depth rating
- 1,200 m
- Range
- 3,400 km
Inspection
SOUNDER
Built to work within a metre of something expensive without touching it.
- Standoff hold
- ± 4 cm
- Depth rating
- 3,000 m
- Current tolerance
- 3.0 kn
Deployment envelope
Where each hull stops
0 M
1,200 M
3,000 M
6,000 M
HALVARD-96,000 M
DRIFTER1,200 M
SOUNDER3,000 M
Specification
Side by side
| Specification | HALVARD-9 | DRIFTER | SOUNDER |
|---|---|---|---|
| Length | 5.85 m | 2.10 m | — |
| Diameter | 0.72 m | — | — |
| Dry mass | 1,180 kg | 62 kg | 540 kg |
| Hull | Ti-6Al-4V, single billet | Carbon over aluminium core | — |
| Transit speed | 3.4 kn | — | — |
| Survey speed | 2.1 kn | — | — |
| Energy | 42 kWh, pressure tolerant | Lithium primary, 9.6 kWh | 28 kWh, or through-tether |
| Navigation | INS with DVL aiding | Dead reckoning, GPS at surface | Doppler and acoustic transponder |
| Recovery | Acoustic release, surface strobe | — | — |
| Turnaround | 6 h deck to deck | — | 90 min deck to deck |
| Wingspan | — | 1.20 m | — |
| Mean speed | — | 0.6 kn | — |
| Dive cycle | — | 4.5 h | — |
| Uplink | — | Iridium, twice daily | — |
| Deployment | — | Two crew, no crane | — |
| Frame | — | — | 1.60 × 1.05 × 0.95 m |
| Thrusters | — | — | 8, vectored |
| Payload capacity | — | — | 70 kg |
| Tether | — | — | Optional, 3,500 m |
| Lighting | — | — | 6 × 18,000 lm |
| Manipulator | — | — | Five function, optional |
Hull selection
Describe the water and the question. Choosing the wrong class is the most expensive decision in a survey campaign, and it is usually made before anyone talks to us.