|
The
Engelhardt Collapsible.
Robert
Hahn
RETTUNGSBOOTE
(Lifeboats)
Taken from
"Schiffbau", Zeitschrift für die gesamte Industrie
auf schiffbautechnischen und verwandten Gebieten,
5. Jahrgang. 1903 – 1904
Published in:
Emil Grottke's Verlag,
Berlin SW. 12,
Wilhelmstrasse 105
Translated by:
Robert Hahn
The
following translation has been shortened from the original source.
Only the part, which deals with the construction of the Engelhardt
Lifeboat has been translated:
[...]
Recently, a new collapsible lifeboat, which
has been developed by a Danish Captain Named V. Engelhardt caused
a stir. This boat has significant advantages compared to other
collapsible boats, that have been used for long time. The Engelhardt
boat has been patented in all the important countries and has
been tested and approved by the Board of Trade. But it is also
produced in Germany by the specifications of the inventor.
The Agent for Germany is Herr Charles Ursin, Hamburg.
The design of the boat can be seen in fig.
1.
Fig.
1. 20' Engelhardt-Boat
The lower part
has been designed as a floating body and avoids the complete
sinking of the boat if it has sprung a leak. It is built up
by a keel (a) and a mid keel (b), two side keels (c) and two
double side planking (d and e), as well as the crossbeams (g
and f). On special demand, an additional protection keel (a1)
will be installed, underneath the keel (a).
The longitudinal
supports (a, b, d and e) are connected and secured to the front
and rear steven (q). The bottom and the top of the lower floating
body are planked (l and i). The planks are run at the bottom,
from stern to bow, and on top of the body diagonally. On top
of this, a layer of canvas has been tightened down (m and n).
The layer on top of the body reaches down 75 mm between the
two side planks (d and e), while the bottom layer reaches up
between (d and e) 75 mm over the edge of the top of the floating
body. On top of the canvas layer, on both sides, two layers
of planking (h and k) are put up. The orientation of the planking
is the same as before. On both sides of the floating body at
the side planks (d and e) are connected strips of wood (p and
o). On these strips of wood are where the fenders (B)
will be fastened. The fenders are build up by short sacks, filled
with Kapok, which are stuffed in the outer coating. Between
the mid keel, the two side keels, and the outer planking are
sacks (A) filled with Kapok too, while the bow and the stern
section of the floating body are filled with cork (C).
The upper part
of the boat has a railing (r) to which a Dollboard (s) is fixed.
The connection of the upper part with the floating body is realized
by 4 hinges (x). The upper cross connection is build up by two
cross parts (t) which are connected to the railing (r). Below
these cross parts are two collapsible supports (u) per side.
Running all around is a seat plank (V) which is made out of
one piece. Connected to the seat planks are cross planks (w).
The water tide canvas on each side is marked by (y).
Fig.
2. 20' Engelhardt-Boat, folded away
Fig.
3. 20' Engelhardt-Boat, folded away, and loaded
with 4000 kg
To make the boat
ready, two men have to lift up the cross parts (t), while doing
this, the seat planks (v) slide down, until they lay on the
hinges (x), which are then fixed by the seat planks. After this,
the 4 collapsible supports (u) have to be pressed into their
tracks.
Fig.
4. 20' Engelhardt-Boat, unfolded
The main advantages
of the "Engelhardt Collapsible Life Boat", which have
been shown during a tough test in England, Denmark, America
and other countries are the following:
1. Several
boats of this type requires the same space on deck as a common
lifeboat, while the number of people, regulated by the
Board of Trade, picked up with the Engelhardt, is higher as
for common boats with the same dimensions.
2. The boat can be unfolded on deck or in the
water in a short time.
3. The boat is absolutely unsinkable, because
the floating body is so calculated, that it still floats with
a great amount of persons as is allowed by the volume of the
boat. This can be proved by the following calculation:
For a 20' boat, the volume is 20' x 7' x 2' 8" x 0.6 =
224 cubic foot.
By the Board of
Trade, 224 / 8 = 28 persons are allowed to be carried against
18 persons in a normal lifeboat with the same dimensions.
The calculations
of the floating body is the following:
19' 6" x 6' 6" x 11" x 0.7 = 81.3 cubic foot
81.3 cubic foot x 63 = 5121,9 pounds
And for the fenders:
44' x 7" diameter
= 11.20 cubic foot
11.20 cubic foot x 63 = 705.6 pounds
together
5827 pounds
the whole boat
weighs approx. 1300 pounds, so that the load capacity is 4527
pounds.
with an average
weight of 150 pounds for a man, a maximum load capacity of 30
persons can be calculated. During countless tests, it could
be proven, that the real capacity is much higher.
26' Engelhardt-boats,
which were delivered to the American Navy, were tested in New
York with more then 8500 pounds, which is 56 persons. A normal
boat of this size can only take 33 persons.
4. In
spite of the fact, that the boats are collapsible, there is
enough space in the boats for water, food and more.
5.
In case of an emergency, normal lifeboats on windward are useless,
while the Engelhardt-boats can be carried over to leeward and
be put into water without using the davits. If there is no time
to set out the boats, it is sufficient enough to cut the fastening.
Then the boats will give the passengers enough time to climb
on, because of their high load capacity.
6. As
a result of their design, the Engelhardt-boats will float even
if they are damage, while a normal boat will leak and sink.
The first prototypes
of the "Engelhardt Collapsible Life Boats" were shown
at the World's fair in Paris in 1900 and became the predicate
"Mention Honorable" - After this, a company was founded
in Copenhagen with the name "The Engelhardt Collapsible
Life Boat Co." and the invention was patented in all important
countries.
The first boat
was on display in Copenhagen in 1901. Here, the Lifesaving
Department, the Navy, several ship insurance companies and all
Danish and other nautical magazines spoke for the boat and predicted
a great future.
In America, the
boat was introduced to the officers of the warship "Illinois".
After this, they ordered from Gibraltar, one of the boat for
trials. This boat was delivered, while the "Illinois"
was docked in Chatham.
At the same time,
the English Admiralty ordered a 20'-boat, which was delivered
to the state shipyard in Portsmouth in May 1903.
After the trial
boat of the "Illinois" was tested under all possibility's
during a period of 8 months, the American Navy ordered a 24'
and a 26'-boat, which was delivered to the shipyard in Boston.
The Commander of
the "Illinois", Captain G. N. Converse, sent the following
report about the trail boat to Washington. The stated flaws
in this report are eliminated in the meanwhile.
SIR:
1. In
accordance with the instructions contained in a letter dated
August 3 rd, 1903, and signed by C. F. Hjort, Mr. Engelhardt's
representative in England, I have this date landed at the Navy
Yard, in care of the Bureau of Construction and Repair, an "Engelhardt
Collapsible Lifeboat", which was loaned to this ship while
in England last summer.
2. For
your information I quote the following from a report made in
regard to this boat:
"The Engelhardt
Collapsible Lifeboat, is, as it's name implies a collapsible
boat, and as such, in my opinion the best of the type.
The one we have
on board is 20' 10" long, 7' 2" beam, and when extended
ready to use, 2' 5" high; but when folded for stowage,
1' high. It weights 810 pounds. It has been tried on several
occasions, and will readily accommodate thirty-five (35) men.
It has been habitually carried on top of the after turret, and
eight men can prepare it for use and launch it."
"I regard
the design of the boat as excellent for the purpose for which
it is intended. The mechanical apertures for distending it requires
remodeling in several details, and the waterproof canvas with
which the boat is covered, is to light and not sufficiently
durable. If these defects are remedied, the boat would in my
opinion, be a serviceable part of the outfit of large vessels.
Yours respectfully.
G. N. Converse,
Captain, U. S. N.
Commanding
[...]
The rest of the article deals with the possibility to use the
boat also for the Army as pontoon bridges.
The
following pictures fig. 5 and 6 show the Engelhardt-boats, which
were used on Titanic. As it can be seen, these boats were slightly
different from the ones described above. Titanic's Engelhardts
had a real hull, which might be a later invention, to give the
boats a better stability at sea. What can also be seen is, that
the inner planking of the floating body was straight, not diagonal
as fig. 1 shows. But it has to be taken into consideration,
that the Engelhardt described in the text might have been an
early prototype, and that until these boats were ordered for
Titanic, 9 years would have passed.
Fig.
5. Titanic's Engelhardt-boat C
Fig.
6. Titanic's Engelhardt-boat A, found by Oceanic
one month after the disaster, still afloat
In
my opinion the article shows, that the Engelhardt-boats were
better then they are always be taken for in Titanic literature.
They were as safe as a sea going lifeboat, and not merely a
weak substitute, which can be also seen by the fact, that Titanic's
Engelhardt boat A stayed afloat for a month, until it was found
by the Oceanic drifting in the open sea with three dead bodies
onboard.
June
2000
Robert Hahn
|